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diff --git a/_posts/posts/2011-01-13-most-likely-to-succeed-in-year-of-2011.md b/_posts/posts/2011-01-13-most-likely-to-succeed-in-year-of-2011.md
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+---
+title: Most likely to succeed in the year of 2011
+permalink: /most-likely-to-succeed-in-year-of-2011.html
+date: 2011-01-13T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+The year of 2010 was definitely the year of Geo-location. The market responded
+beautifully and lots of very cool services were launched. We all have to thank
+the mobile market for such extensive adoption. With new generations of mobile
+phones that are not only buffed with high-tech hardware but are also affordable.
+We can now manage tasks that were not so long time ago, almost Star Trek’ish.
+And all this had and has great influence on the destination to which we are
+going now.
+
+Reading all this articles about new innovation about new thriving technologies
+makes me wonder what’s the next step. The future is the mesh, like Lisa Gansky
+said in her book The Mesh.
+
+Many still have conservative views on distributed systems. The problems with
+security of information. Fear of not controlling every aspect of information
+flow. I am very opened to distributed systems and heterogeneous applications,
+and I think this is the correct and best way to proceed.
+
+This year will definitely be about communication platforms. Mobile to mobile.
+Machine to mobile and vice versa. All the tech is available and ready to put
+into action. Wireless is today’s new mantra. And the concept of semantic web is
+now ready for industry.
+
+Applications and developers now can gain access to new layers of systems and can
+prepare and build solutions to meet the high quality needs of market. The speed
+is everything now.
+
+My vote goes to “Machine to Machine” and “Embedded Systems”!
+
+- [Machine-to-Machine](http://en.wikipedia.org/wiki/Machine-to-Machine)
+- [The ultimate M2M communication protocol](http://www.bitxml.org/)
+- [COOS Project (connectivity initiative)](http://www.coosproject.org/maven-site/1.0.0/project-info.html)
+- [Community for machine-to-machine](http://m2m.com/index.jspa)
+- [Embedded system](http://en.wikipedia.org/wiki/Embedded_system)
+
diff --git a/_posts/posts/2012-03-09-led-technology-not-so-eco.md b/_posts/posts/2012-03-09-led-technology-not-so-eco.md
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+---
+title: LED technology might not be as eco-friendly as you think
+permalink: /led-technology-not-so-eco.html
+date: 2012-03-09T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+There is a lot of talk about LED technology. It is beginning to infiltrate
+industry at a fast rate, and it’s a challenge for designers and also engineers.
+I wondered when a weakness will be revealed. Then I stomped on an article
+talking about harm in using LED technology. It looks like this magical
+technology is not so magical and eco-friendly.
+
+A new study from the University of California indicates that LED lights contain
+toxic metals, and should be produced, used and disposed of carefully.  Besides
+the lead and nickel, the bulbs and their associated parts were also found to
+contain arsenic, copper, and other metals that have been linked to different
+cancers, neurological damage, kidney disease, hypertension, skin rashes and
+other illnesses in humans, and to ecological damage in waterways.
+
+Since then, I haven’t yet found any regulation for disposal of LED lights or any
+other regulation or standard. This might be a problem in the future. And it is a
+massive drawback. This might have quite an impact on consumer market.
+
+Nevertheless, there is a potential, and I am sure the market will adapt. I also
+hope I will be reading documents regarding solution for this concern soon.
+
+**Additional resources:**
+
+- [Recycling and Disposal of Light Bulbs](http://ezinearticles.com/?Recycling-and-Disposal-of-Light-Bulbs&id=1091304)
+- [How to Dispose of a Low-Energy Light Bulb](http://www.ehow.com/how_7483442_dispose-lowenergy-light-bulb.html)
+
diff --git a/_posts/posts/2013-10-24-wireless-sensor-networks.md b/_posts/posts/2013-10-24-wireless-sensor-networks.md
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+---
+title: Wireless sensor networks
+permalink: /wireless-sensor-networks.html
+date: 2013-10-24T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+Zigbee networks have this wonderful capability to self-heal, which means they
+can reorder connections between them if one of them is inoperable. This works
+our of the box when you deploy them. But you have to have in mind that achieving
+this is not as easy as you would think. None of it is plug&play.  So to make
+your life a bit easier, here are some pointers which, I hope, will help you.
+
+- Be careful when you are ordering your equipment abroad. There are many rules
+  and regulations you need to comply before you get your Xbee radios. What they
+  do is they wait until you prove that you won’t use the technology for some
+  kind of evil take over control of the world project :). For this, they have
+  EAR (Export Administration Regulations) which basically means “This product
+  may require a license to export from the United States.”.
+- I don’t know if this applies for every country, but when we purchased our Xbee
+  radios from Mouser, this was mandatory! What we needed to do was to print out
+  a form and write information about our company and send them a copy via
+  email. With this document, we proved that we are a legitimate company.
+- When you complete your purchase and send all the documentation, you are not
+  clear yet. Then customs will take it from there :). There will be some
+  additional costs. Before purchasing, make sure you have as much information
+  about costs as possible. Because it can get costly in the end.
+- I suggest you use companies from your country. You can seriously cut your
+  costs. Here in Slovenia, the best option so far as I know is Farnell. And
+  based on my personal experience, they rock! All I need to say!
+- Make plans when ordering larger quantities. Do not, I say, do not make your
+  orders in December! :) Believe me! You will have problems with stock they can
+  provide for you. So, we were forced to buy some things from Mouser, which was
+  extremely painful because of all the regulations you need to obey when
+  importing goods from the USA.
+- Make sure that firmware version on your Xbee radios is exactly the same! Do
+  not get creative!!! I propose using templates. You can get template by
+  exporting settings/profile in X-CTU application. Make sure you have enabled
+  “Upgrade firmware” so you can be sure each radio has the same firmware.
+- And again: make plans! Plan everything! In months advanced! You will thank me
+  later :)
+- Test, test, test. Wireless networks can be tricky.
+
+If you are serious, I suggest you buy this book, Building Wireless Sensor
+Networks. You will get a glimpse of how networks work in lumens terms. It is a
+good starting point for everybody who wants to build wireless networks.
+
+**Additional resources:**
+
+- http://www.digi.com/aboutus/export/generalexportinfo
+- http://doresearch.stanford.edu/research-scholarship/export-controls/export-controlled-or-embargoed-countries-entities-and-persons
+- http://www.bis.doc.gov/licensing/exportingbasics.htm
+
diff --git a/_posts/posts/2015-11-10-software-development-pitfalls.md b/_posts/posts/2015-11-10-software-development-pitfalls.md
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+---
+title: Software development and my favorite pitfalls
+permalink: /software-development-pitfalls.html
+date: 2015-11-10T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+Over the years I had the privilege to work on some very excited projects both in
+software development field and also in electronics field and every experience
+taught me some invaluable lessons about how NOT TO approach development. And
+through this post I will try to point out some absurd, outdated techniques I
+find the most annoying and damaging during a development cycle. There will be
+swearing because this topic really gets on my nerves and I never coherently
+tried to explain them in writing. So if I get heated up, please bear with me.
+
+As new methods of project management are emerging, underlying processes still
+stay old and outdated. This is mainly because we as people are unable to
+completely shift away from these approaches.
+
+I was always struggling with communication, and many times that cost me a
+relationship or two because I was not on the ball all the time. Through every
+experience, I became more convinced that I am the problem and never ever doubted
+that the problem may be that communication never evolved a single step from
+emails. And if you think for a second, not many things have changed around this
+topic. We just have different representations of email (message boards, chats,
+project management tools). And I believe this is the real issue we are facing
+now.
+
+There are many articles written about hyper connectivity and the effects that
+are a direct result of it. But mainstream does nothing towards it. We are just
+putting out fires, and we do nothing to prevent it. I am certain this will be a
+major source of grief in coming years. And what we all can do to avoid this is
+to change our mindset and experiment on our communication skills, development
+approaches. We need to maximize possible output that a person can give. And to
+achieve this we need to listen to them, encourage them. I know that not
+everybody is a naturally born leader, but with enough practice and encouragement
+they also can become active participants in leadership.
+
+There are many talks now about methodologies such as Scrum, Kanban, Cleanroom
+and they all fucking piss me of :). These are all boxes that imprison people and
+take away their freedom of thought. This is a straightforward mindfuck /
+amputation of creativity.
+
+Let me list a couple of things that I find really destructive and bad for a
+project and in a long run company.
+
+## Ping emails
+
+Ping emails are emails you have to write as soon as you receive an email. Its
+sole purpose is to inform the sender that you received their email, and you are
+working on it. Its result is only to calm down the sender that their task is
+being dealt with. It’s intent basically is, I did my job by sending you this
+email, so I am on clear grounds. I categorize this email as fuck you email.
+This is one of the most irritating types of emails I need to write. This is the
+ultimate control freak show you can experience, and it gives the sender a false
+feeling of control. Newsflash: We do not live in 1982 where there was a
+possibility that email never reached the destination. I really hate this from
+the bottom of my heart.
+
+They should be like: “Yes, I am fucking alive, and I am at your service my
+leash!”. I guess if I would reply like this, I wouldn’t have to write any more
+of this kind of messages.
+
+## Everybody is a project manager
+
+Well, this is a tough one. I noticed that as soon as you let people to give
+their suggestions, you are basically screwed. There is a truth in the saying:
+“Give low expectations and deliver little more than you promised.”.
+
+People tend to take a role of a manager as soon as they are presented with an
+opportunity. And by getting angry at them, you only provoke yourself. They are
+not at fault. You just need to tell them they are only giving suggestions and
+not tasks at the beginning and everything will be alright. But if you give them
+a feeling that they are in control, you will have immense problems explaining
+why their features are not in current release.
+
+Project mission must be always leading project requirements and any deviation
+from it will result in major project butchering. And by this, I mean that the
+project will get its own path, and you will be left with half done software that
+helps nobody. Clear mission goals and clean execution will allow you to develop
+software will clear intent.
+
+## We are never wrong
+
+I find this type of arrogance the worst. We must always conduct ourselves that
+we are infallible and cannot make mistakes. As soon as a procedure or process is
+established, there is no room for changes or improvements. This is the most
+idiotic thing someone can say of think. I think that processes need to involve
+and change over time. This is imperative and need to have in your organization
+if you want to improve and develop company. We all need to grow balls and change
+everything in order to adapt to current situations. Being a prisoner of
+predefined processes kills creativity.
+
+I am constantly trying new software for project managing and communication.  I
+believe every team has its own dynamic, and it needs to be discovered
+organically and naturally through many experiments. By putting the team in a
+box, you are amputating their creativity and therefore minimizing their
+potential. But if you talk to an executive, you will mainly find archetypical
+thinking and a strong need to compartmentalize everything from business
+processes to resource management. And this type of management that often
+displays micromanagement techniques only works for short periods (couple of
+years) and then employees either leave the company or become basically retarded
+drones on autopilot.
+
+## Micromanaging
+
+This basically implies that everybody on the team is an idiot who needs to have
+a to-do list that they cannot write themselves. How about spoon-feeding the team
+at launch because besides the team leader, everybody must be a retarded idiot at
+best?
+
+I prefer milestones as they give developers much more freedom and creativity in
+developing and not waste their time checking some bizarre to-do list that was
+not even thought through. Projects constantly change throughout the development
+cycle, and all you are left at the end is a list of unchecked tasks and the
+wrath of management why they are not completed. Best WTF moment!
+
+## Human contact — no need for it!
+
+We are vigorously trying to eliminate physical contact by replacing short
+meetings with software, with no regards that we are not machines. Many times a
+simple 5-min meeting at morning can solve most of the problems. In rapid
+development, short bursts of man to man communication is possibly the best way
+to go.
+
+We now have all this software available, and all what we get out of it is a
+giant clusterfuck. An obstacle and not a solution. So, why we still use them?
+
+## MVP is killing innovation
+
+Many will disagree with me on this one, but I stand strong by this statement.
+What I noticed in my experience that all this buzz words around us only mislead
+and capture us in a circle of solving issues that already have a solution, but
+we are unable to see it without using some fancy word for it.
+
+The toughest thing to do for a developer is to minimize requirements. Well, this
+is though only for bad developers. Yes, I said it. There are many types of
+developers out there. And those unable to minimize feature scope are the ones
+you don’t need on your team. Their only goal is to solve problems that exist
+only in their heads. And then you have to argue with them, and waste energy on
+them, instead of developing your awesome product. They are a cancer and I
+suggest you cut them off.
+
+MVP as an idea is great, but sadly people don’t understand underlying
+philosophy, and they spent too much time focusing and fixating on something that
+every sane person with normal IQ will understand without some made up
+acronym. And the result is a lot of talking and barely no execution.
+
+Well, MVP is not directly killing innovation, but stupid people do when they try
+to understand it.
+
+## Pressure wasteland
+
+You must never allow to be pressured into confirming a deadline if you are not
+confident. We often feel a need that we are in service of others, which is true
+to some extent. But it is also true that others are in service to us to some
+extent. And we forget this all the time. We are all pressured all the time to
+make decisions just to calm other people down. And when they leave your office
+you experience WTF moment :) How the hell did they manage to fuck me up again?
+
+People need to realize that the more pressure you put on somebody, the less they
+will be able to do. So 5-min update email requests will only resolve in mental
+breakdown and inability to work that day. Constant poking is probably the only
+thing I lose my mind instantly. For all you that are doing this: “Stop bothering
+us with your insecurities and let us do our job. We will do it quicker and
+better without you breathing down our necks.”
+
+If this happens to me, I end up with no energy at the end. Don’t you get it?
+You will get much more from and out of me if you ask me like a human person and
+not your personal butler. On a long run, you are destroying your relationships
+and nobody would want to work with you. Your schizophrenic approach will damage
+only you in a long run. Nobody is anybody’s property.
+
+## Conclusion
+
+I am guilty of many things described in this post. And I find it hard sometimes
+to acknowledge this. And I lie to myself and try vigorously to find some
+explanation why I do these things. There is always space for growth. And maybe
+you will also find some of yourself in this post and realize what needs to
+change for you to evolve.
diff --git a/_posts/posts/2017-03-07-golang-profiling-simplified.md b/_posts/posts/2017-03-07-golang-profiling-simplified.md
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+---
+title: Golang profiling simplified
+permalink: /golang-profiling-simplified.html
+date: 2017-03-07T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+Many posts have been written regarding profiling in Golang and I haven’t found
+proper tutorial regarding this. Almost all of them are missing some part of
+important information and it gets pretty frustrating when you have a deadline
+and are not finding simple distilled solution.
+
+Nevertheless, after searching and experimenting I have found a solution that
+works for me and probably should also for you.
+
+## Where are my pprof files?
+
+By default pprof files are generated in /tmp/ folder. You can override folder
+where this files are generated programmatically in your golang code as we will
+see below in example.
+
+## Why is my CPU profile empty?
+
+I have found out that sometimes CPU profile is empty because program was not
+executing long enough. Programs, that execute too quickly don’t produce pprof
+file in my cases. Well, file is generated but only contains 4KB of information.
+
+## Profiling
+
+As you can see from examples we are executing dummy_benchmark functions to
+ensure some sort of execution. Memory profiling can be done without such a
+“complex” function. But CPU profiling needs it.
+
+Both memory and CPU profiling examples are almost the same. Only parameters in
+main function when calling profile.Start are different. When we set
+profile.ProfilePath(“.”) we tell profiler to store pprof files in the same
+folder as our program.
+
+### Memory profiling
+
+```go
+package main
+
+import (
+  "fmt"
+  "time"
+  "github.com/pkg/profile"
+)
+
+func dummy_benchmark() {
+
+  fmt.Println("first set ...")
+  for i := 0; i < 918231333; i++ {
+    i *= 2
+    i /= 2
+  }
+
+  <-time.After(time.Second*3)
+
+  fmt.Println("sencond set ...")
+  for i := 0; i < 9182312232; i++ {
+    i *= 2
+    i /= 2
+  }
+}
+
+func main() {
+  defer profile.Start(profile.MemProfile, profile.ProfilePath("."), profile.NoShutdownHook).Stop()
+  dummy_benchmark()
+}
+```
+
+### CPU profiling
+
+```go
+package main
+
+import (
+  "fmt"
+  "time"
+  "github.com/pkg/profile"
+)
+
+func dummy_benchmark() {
+
+  fmt.Println("first set ...")
+  for i := 0; i < 918231333; i++ {
+    i *= 2
+    i /= 2
+  }
+
+  <-time.After(time.Second*3)
+
+  fmt.Println("sencond set ...")
+  for i := 0; i < 9182312232; i++ {
+    i *= 2
+    i /= 2
+  }
+}
+
+func main() {
+  defer profile.Start(profile.CPUProfile, profile.ProfilePath("."), profile.NoShutdownHook).Stop()
+  dummy_benchmark()
+}
+```
+
+### Generating profiling reports
+
+```bash
+# memory profiling
+go build mem.go
+./mem
+go tool pprof -pdf ./mem mem.pprof > mem.pdf
+
+# cpu profiling
+go build cpu.go
+./cpu
+go tool pprof -pdf ./cpu cpu.pprof > cpu.pdf
+```
+
+This will generate PDF document with visualized profile.
+
+- [Memory PDF profile example](/assets/posts/go-profiling/golang-profiling-mem.pdf)
+- [CPU PDF profile example](/assets/posts/go-profiling/golang-profiling-cpu.pdf)
+
diff --git a/_posts/posts/2017-04-17-what-i-ve-learned-developing-ad-server.md b/_posts/posts/2017-04-17-what-i-ve-learned-developing-ad-server.md
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+---
+title: What I've learned developing ad server
+permalink: /what-i-ve-learned-developing-ad-server.html
+date: 2017-04-17T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+For the past year and half I have been developing native advertising server that
+contextually matches ads and displays them in different template forms on
+variety of websites. This project grew from serving thousands of ads per day to
+millions.
+
+The system is made from couple of core components:
+
+- API for serving ads,
+- Utils - cronjobs and queue management tools,
+- Dashboard UI.
+
+Initial release was using [MongoDB](https://www.mongodb.com/) for full-text
+search but was later replaced by [Elasticsearch](https://www.elastic.co/) for
+better CPU utilization and better search performance. This provided us with many
+amazing functionalities of [Elasticsearch](https://www.elastic.co/).  You should
+check it out if you do any search related operations.
+
+Because the premise of the server is to provide native ad experience, they are
+rendered on the client side via simple templating engine. This ensures that ads
+can be displayed number of different ways based on the visual style of the
+page. And this makes JavaScript client library quite complex.
+
+So now that you know basic information about the product lets get into the
+lessons we learned.
+
+## Aggregate everything
+
+After beta version was released everything (impressions, clicks, etc) was
+written in nanosecond resolution in the database. At that time we were using
+[PostgreSQL](https://www.postgresql.org/) and database quickly grew way above
+200GB in disk space. And that was problematic. Statistics took disturbingly long
+time to aggregate. Also using indexes on stats table in database was no help
+after we reached 500 million datapoints.
+
+> There is a marketing product information and there is real life experience.
+And the tend to be quite the opposite.
+
+This was the reason that now everything is aggregated on daily basis and this
+data is then fed to Elastic in form of daily summary. With this we achieved we
+can now track many more dimensions such as zone, channel and platform
+information.  And with this information we can now adapt occurrences of ads on
+specific places more precisely.
+
+We have also adapted [Redis](https://redis.io/) as a full-time citizen in our
+stack. Because Redis also stores information on a local disk we have some sort
+of backup if server would accidentally suffer some failure.
+
+All the real-time statistics for ad serving and redirecting is presented as
+counters in Redis instance and daily extracted and pushed to Elastic.
+
+## Measure everything
+
+The thing about software is that we really don't know how well it is performing
+under load until such load is presented. When testing locally everything is fine
+but when on production things tend to fall apart.
+
+As a solution for this we are measuring everything we can. Function execution
+time (by encapsulating functions with timers), server performance (cpu, memory,
+disk, etc), Nginx and [uWSGI](https://uwsgi-docs.readthedocs.io/) performance.
+We sacrifice a bit of performance for the sake of this information. And we store
+all this information for later analysis.
+
+**Example of function execution time**
+
+```json
+{
+  "get_final_filtered_ads": {
+    "counter": 1931250,
+    "avg": 0.0066143431,
+    "elapsed": 12773.9500310003
+  },
+  "store_keywords_statistics": {
+    "counter": 1931011,
+    "avg": 0.0004605267,
+    "elapsed": 889.2821669996
+  },
+  "match_by_context": {
+    "counter": 1931011,
+    "avg": 0.0055960716,
+    "elapsed": 10806.0758889999
+  },
+  "match_by_high_performance": {
+    "counter": 262,
+    "avg": 0.0152770229,
+    "elapsed": 4.00258
+  },
+  "store_impression_stats": {
+    "counter": 1931250,
+    "avg": 0.0006189991,
+    "elapsed": 1195.4419869999
+  }
+}
+```
+
+We have also started profiling with [cProfile](https://pymotw.com/2/profile/)
+and then visualizing with [KCachegrind](http://kcachegrind.sourceforge.net/).
+This provides much more detailed look into code execution.
+
+## Cache control is your friend
+
+Because we use Javascript library for rendering ads we rely on this script
+extensively and when in need we need to be able to change behavior of the script
+quickly.
+
+In our case we can not simply replace javascript url in html code. It usually
+takes a day or two for the guys who maintain sites to change code or add
+?ver=xxx attribute. And this makes rapid deployment and testing very difficult
+and time consuming. There is a limitation of how much you can test locally.
+
+We are now in the process of integrating [Google Tag
+Manager](https://www.google.com/analytics/tag-manager/) but couple of websites
+are developed on ASP.net platform that have some problems with tag manager. With
+a solution below we are certain that we are serving latest version of the
+script.
+
+And it only takes one mistake and users have the script cached and in case of
+caching it for 1 year you probably know where the problem is.
+
+```nginx
+# nginx ➜ /etc/nginx/sites-available/default
+location /static/ {
+  alias /path-to-static-content/;
+  autoindex off;
+  charset utf-8;
+  gzip on;
+  gzip_types text/plain application/javascript application/x-javascript text/javascript text/xml text/css;
+  location ~* \.(ico|gif|jpeg|jpg|png|woff|ttf|otf|svg|woff2|eot)$ {
+    expires 1y;
+    add_header Pragma public;
+    add_header Cache-Control "public";
+  }
+  location ~* \.(css|js|txt)$ {
+    expires 3600s;
+    add_header Pragma public;
+    add_header Cache-Control "public, must-revalidate";
+  }
+}
+```
+
+Also be careful when redirecting to url in your python code. We noticed that if
+we didn't precisely setup cache control and expire headers in response we didn't
+get the request on the server and therefore couldn't measure clicks.  So when
+redirecting do as follows and there will be no problems.
+
+```python
+# python ➜ bottlepy web micro-framework
+response = bottle.HTTPResponse(status=302)
+response.set_header("Cache-Control", "no-store, no-cache, must-revalidate")
+response.set_header("Expires", "Thu, 01 Jan 1970 00:00:00 GMT")
+response.set_header("Location", url)
+return response
+```
+
+> Cache control in browsers is quite aggressive and you need to be precise to
+avoid future problems. We learned that lesson the hard way.
+
+## Learn NGINX
+
+When deciding on a web server we went with Nginx as a reverse proxy for our
+applications. We adapted micro-service oriented architecture early in the
+project to ensure when we scale we can easily add additional servers to our
+cluster. And Nginx was crucial to perform load balancing and static content
+delivery.
+
+At first our config file was quite simple and later grew larger. After patching
+and adding new settings I sat down and learned more about the guts of Nginx.
+This proved to be very useful and we were able to squeeze much more out of our
+setup. So I advise you to take your time and read through the
+[documentation](https://nginx.org/en/docs/). This saved us a lot of headache.
+Googling for solutions only goes so far.
+
+## Use Redis/Memcached
+
+As explained above we are using caching basically for everything. It is the
+corner stone of our services. At first we were very careful about the quantity
+of things we stored in [Redis](https://redis.io/). But we later found out that
+the memory footprint is very low even when storing large amount of data in it.
+
+So we gradually increased our usage to caching whole HTML outputs of dashboard.
+This improved our performance in order of magnitude. And by using native TTL
+support this goes hand in hand with our needs.
+
+The reason why we choose [Redis](https://redis.io/) over
+[Memcached](https://memcached.org/) was the nature of scalability of Redis out
+of the box. But all this can be achieved with Memcached.
+
+## Conclusion
+
+There are a lot more details that could have been written and every single topic
+in here deserves it's own post but you probably got the idea about the problems
+we faced.
diff --git a/_posts/posts/2017-04-21-profiling-python-web-applications-with-visual-tools.md b/_posts/posts/2017-04-21-profiling-python-web-applications-with-visual-tools.md
new file mode 100644
index 0000000..2e2ec70
--- /dev/null
+++ b/_posts/posts/2017-04-21-profiling-python-web-applications-with-visual-tools.md
@@ -0,0 +1,207 @@
+---
+title: Profiling Python web applications with visual tools
+permalink: /profiling-python-web-applications-with-visual-tools.html
+date: 2017-04-21T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+I have been profiling my software with KCachegrind for a long time now and I was
+missing this option when I am developing API's or other web services. I always
+knew that this is possible but never really took the time and dive into it.
+
+Before we begin there are some requirements. We will need to:
+
+- implement [cProfile](https://docs.python.org/2/library/profile.html#module-cProfile) into our web app,
+- convert output to [callgrind](http://valgrind.org/docs/manual/cl-manual.html) format with [pyprof2calltree](https://pypi.python.org/pypi/pyprof2calltree/),
+- visualize data with [KCachegrind](http://kcachegrind.sourceforge.net/html/Home.html) or [Profiling Viewer](http://www.profilingviewer.com/).
+
+
+If you are using MacOS you should check out [Profiling
+Viewer](http://www.profilingviewer.com/) or
+[MacCallGrind](http://www.maccallgrind.com/).
+
+![KCachegrind](/assets/posts/python-profiling/kcachegrind.png){:loading="lazy"}
+
+We will be dividing this post into two main categories:
+
+- writing simple web-service,
+- visualize profile of this web-service.
+
+## Simple web-service
+
+Let's use virtualenv so we won't pollute our base system. If you don't have
+virtualenv installed on your system you can install it with pip command.
+
+```bash
+# let's install virtualenv globally
+$ sudo pip install virtualenv
+
+# let's also install pyprof2calltree globally
+$ sudo pip install pyprof2calltree
+
+# now we create project
+$ mkdir demo-project
+$ cd demo-project/
+
+# now let's create folder where we will store profiles
+$ mkdir prof
+
+# now we create empty virtualenv in venv/ folder
+$ virtualenv --no-site-packages venv
+
+# we now need to activate virtualenv
+$ source venv/bin/activate
+
+# you can check if virtualenv was correctly initialized by
+# checking where your python interpreter is located
+# if command bellow points to your created directory and not some
+# system dir like /usr/bin/python then everything is fine
+$ which python
+
+# we can check now if all is good ➜ if ok couple of
+# lines will be displayed
+$ pip freeze
+# appdirs==1.4.3
+# packaging==16.8
+# pyparsing==2.2.0
+# six==1.10.0
+
+# now we are ready to install bottlepy ➜ web micro-framework
+$ pip install bottle
+
+# you can deactivate virtualenv but you will then go
+# under system domain ➜ for now don't deactivate
+$ deactivate
+```
+
+We are now ready to write simple web service. Let's create file app.py and paste
+code bellow in this newly created file.
+
+```python
+# -*- coding: utf-8 -*-
+
+import bottle
+import random
+import cProfile
+
+app = bottle.Bottle()
+
+# this function is a decorator and encapsulates function
+# and performs profiling and then saves it to subfolder
+# prof/function-name.prof
+# in our example only awesome_random_number function will
+# be profiled because it has do_cprofile defined
+def do_cprofile(func):
+  def profiled_func(*args, **kwargs):
+    profile = cProfile.Profile()
+    try:
+      profile.enable()
+      result = func(*args, **kwargs)
+      profile.disable()
+      return result
+    finally:
+      profile.dump_stats("prof/" + str(func.__name__) + ".prof")
+  return profiled_func
+
+
+# we use profiling over specific function with including
+# @do_cprofile above function declaration
+@app.route("/")
+@do_cprofile
+def awesome_random_number():
+  awesome_random_number = random.randint(0, 100)
+  return "awesome random number is " + str(awesome_random_number)
+
+@app.route("/test")
+def test():
+  return "dummy test"
+
+if __name__ == '__main__':
+  bottle.run(
+    app = app,
+    host = "0.0.0.0",
+    port = 4000
+  )
+
+# run with 'python app.py'
+# open browser 'http://0.0.0.0:4000'
+```
+
+When browser hits awesome\_random\_number() function profile is created in prof/
+subfolder.
+
+## Visualize profile
+
+Now let's create callgrind format from this cProfile output.
+
+```bash
+$ cd prof/
+$ pyprof2calltree -i awesome_random_number.prof
+# this creates 'awesome_random_number.prof.log' file in the same folder
+```
+
+This file can be opened with visualizing tools listed above. In this case we
+will be using Profilling Viewer under MacOS. You can open image in new tab.  As
+you can see from this example there is hierarchy of execution order of your
+code.
+
+![Profilling Viewer](/assets/posts/python-profiling/profiling-viewer.png){:loading="lazy"}
+
+> Make sure you convert output of the cProfile output every time you want to
+refresh and take a look at your possible optimizations because cProfile updates
+.prof file every time browser hits the function.
+
+This is just a simple example but when you are developing real-life applications
+this can be very illuminating, especially to see which parts of your code are
+bottlenecks and need to be optimized.
+
+## Update 2017-04-22
+
+Reddit user [mvt](https://www.reddit.com/user/mvt) also recommended this awesome
+web based profile visualizer [SnakeViz](https://jiffyclub.github.io/snakeviz/)
+that directly takes output from
+[cProfile](https://docs.python.org/2/library/profile.html#module-cProfile)
+module.
+
+<div class="reddit-embed" data-embed-media="www.redditmedia.com" data-embed-parent="false" data-embed-live="false" data-embed-uuid="583880c1-002e-41ed-a373-020a0ef2cff9" data-embed-created="2017-04-22T19:46:54.810Z"><a href="https://www.reddit.com/r/Python/comments/66v373/profiling_python_web_applications_with_visual/dgljhsb/">Comment</a> from discussion <a href="https://www.reddit.com/r/Python/comments/66v373/profiling_python_web_applications_with_visual/">Profiling Python web applications with visual tools</a>.</div><script async src="https://www.redditstatic.com/comment-embed.js"></script>
+
+```bash
+# let's install it globally as well
+$ sudo pip install snakeviz
+
+# now let's visualize
+$ cd prof/
+$ snakeviz awesome_random_number.prof
+# this automatically opens browser window and
+# shows visualized profile
+```
+
+![SnakeViz](/assets/posts/python-profiling/snakeviz.png){:loading="lazy"}
+
+Reddit user [ccharles](https://www.reddit.com/user/ccharles) suggested a better
+way for installing pip software by targeting user level instead of using sudo.
+
+<div class="reddit-embed" data-embed-media="www.redditmedia.com" data-embed-parent="false" data-embed-live="false" data-embed-uuid="f4f0459e-684d-441e-bebe-eb49b2f0a31d" data-embed-created="2017-04-22T19:46:10.874Z"><a href="https://www.reddit.com/r/Python/comments/66v373/profiling_python_web_applications_with_visual/dglpzkx/">Comment</a> from discussion <a href="https://www.reddit.com/r/Python/comments/66v373/profiling_python_web_applications_with_visual/">Profiling Python web applications with visual tools</a>.</div><script async src="https://www.redditstatic.com/comment-embed.js"></script>
+
+```bash
+# now we need to add this path to our $PATH variable
+# we do this my adding this line at the end of your
+# ~/.bashrc file
+PATH=$PATH:$HOME/.local/bin/
+
+# in order to use this new configuration you can close
+# and reopen terminal or reload .bashrc file
+$ source ~/.bashrc
+
+# now let's test if new directory is present in $PATH
+$ echo $PATH
+
+# now we can install on user level by adding --user
+# without use of sudo
+$ pip install snakeviz --user
+```
+
+Or as suggested by [mvt](https://www.reddit.com/user/mvt) you can 
+use [pipsi](https://github.com/mitsuhiko/pipsi).
diff --git a/_posts/posts/2017-08-11-simple-iot-application.md b/_posts/posts/2017-08-11-simple-iot-application.md
new file mode 100644
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--- /dev/null
+++ b/_posts/posts/2017-08-11-simple-iot-application.md
@@ -0,0 +1,608 @@
+---
+title: Simple IOT application supported by real-time monitoring and data history
+permalink: /simple-iot-application.html
+date: 2017-08-11T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Initial thoughts
+
+I have been developing these kind of application for the better part of my last
+5 years and people keep asking me how to approach developing such application
+and I will give a try explaining it here.
+
+IOT applications are really no different than any other kind of applications.
+We have data that needs to be collected and visualized in some form of tables or
+charts. The main difference here is that most of the times these data is
+collected by some kind of device foreign to developer that mainly operates in
+web domain. But fear not, it's not that different than writing some JavaScript.
+
+There are many devices able to transmit data via wireless or wired network by
+default but for the sake of example we will be using commonly known Arduino with
+wireless module already on the board → [Arduino
+MKR1000](https://store.arduino.cc/arduino-mkr1000).
+
+In order to make this little project as accessible to others as possible I will
+try to make it as inexpensive as possible. And by this I mean that I will avoid
+using hosted virtual servers and will be using my own laptop as a server. But
+you must buy Arduino MKR1000 to follow steps below. But if you would want to
+deploy this software I would suggest using
+[DigitalOcean](https://www.digitalocean.com) → smallest VPS is only per month
+making this one of the most affordable option out there. Please notice that this
+software will not run on stock web hosting that only supports LAMP (Linux,
+Apache, MySQL, and PHP).
+
+But before we begin please take notice that this is strictly experimental code
+and not well optimized and there are much better ways in handling some aspects
+of the application but that requires much deeper knowledge of technology that is
+not needed for an example like this.
+
+**Development steps**
+
+1. Simple Python API that will receive and store incoming data.
+2. Prototype C++ code that will read "sensor data" and transmit it to API.
+3. Data visualization with charts → extends Python web application.
+
+Step 1. and 3. will share the same web application. One route will be dedicated
+to API and another to serving HTML with chart.
+
+Schema below represents what we will try to achieve and how different parts
+correlates to each other.
+
+![Overview](/assets/posts/iot-application/simple-iot-application-overview.svg){:loading="lazy"}
+
+## Simple Python API
+
+I have always been a fan of simplicity so we will be using [Bottle: Python Web
+Framework](https://bottlepy.org/docs/dev/).  It is a single file web framework
+that seriously simplifies working with routes, templating and has built-in web
+server that satisfies our need in this case.
+
+First we need to install bottle package. This can be done by downloading
+```bottle.py``` and placing it in the root of your application or by using pip
+software ```pip install bottle --user```.
+
+If you are using Linux or MacOS then Python is already installed. If you will
+try to test this on Windows please install [Python for
+Windows](https://www.python.org/downloads/windows/).  There may be some problems
+with path when you will try to launch ```python webapp.py``` so please take care
+of this before you continue.
+
+### Basic web application
+
+Most basic bottle application is quite simple. Paste code below in
+```webapp.py``` file and save.
+
+```python
+# -*- coding: utf-8 -*-
+
+import bottle
+
+# initializing bottle app
+app = bottle.Bottle()
+
+# triggered when / is accessed from browser
+# only accepts GET → no POST allowed
+@app.route("/", method=["GET"])
+def route_default():
+  return "howdy from python"
+
+# starting server on http://0.0.0.0:5000
+if __name__ == "__main__":
+  bottle.run(
+    app = app,
+    host = "0.0.0.0",
+    port = 5000,
+    debug = True,
+    reloader = True,
+    catchall = True,
+  )
+```
+
+To run this simple application you should open command prompt or terminal on
+your machine and go to the folder containing your file and type ```python
+webapp.py```. If everything goes ok then open your web browser and point it to
+```http://0.0.0.0:5000```.
+
+If you would like change the port of your application (like port 80) and not use
+root to run your app this will present a problem. The TCP/IP port numbers below
+1024 are privileged ports → this is a security feature. So in order of
+simplicity and security use a port number above 1024 like I have used port 5000.
+
+If this fails at any time please fix it before you continue, because nothing
+below will work otherwise.
+
+We use 0.0.0.0 as default host so that this app is available over your local
+network. If you find your local ip ```ifconfig``` and try accessing this site
+with your phone (if on same network/router as your machine) this should work as
+well (example of such ip ```http://192.168.1.15:5000```). This is a must have
+because Arduino will be accessing this application to send it's data.
+
+### Web application security
+
+There is a lot to be said about security and is a topic of many books. Of course
+all this can not be written here but to just establish some basic security → you
+should always use SSL with your application. Some fantastic free certificates
+are available by [Let's Encrypt - Free SSL/TLS
+Certificates](https://letsencrypt.org).  With SSL certificate installed you
+should then make use of HTTP headers and send your "API key" via a header. If
+your key is send via header then this key is encrypted by SSL and send encrypted
+over the network. Never send your api keys by GET parameter like
+```http://example.com/?api_key=somekeyvalue```.  The problem that this kind of
+sending presents is that this key is visible in logs and by network sniffers.
+
+There is a fantastic article describing some aspects about security: [11 Web
+Application Security Best
+Practices](https://www.keycdn.com/blog/web-application-security-best-practices/). Please
+check it out.
+
+### Simple API for writing data-points
+
+We will now be using boilerplate code from example above and extend it to be
+SQLite3 because it plays well with Python and can store quite large amount of
+able to write data received by API to local storage. For example use I will use
+data. I have been using it to collect gigabytes of data in a single database
+without any corruption or problems → your experience may vary.
+
+To avoid learning SQLite I will be using [Dataset: databases for lazy
+people](https://dataset.readthedocs.io/en/latest/index.html).  This package
+abstracts SQL and simplifies writing and reading data from database. You should
+install this package with pip software ```pip install dataset --user```.
+
+Because API will use POST method I will be testing if code works correctly by
+using [Restlet Client for Google
+Chrome](https://chrome.google.com/webstore/detail/restlet-client-rest-api-t/aejoelaoggembcahagimdiliamlcdmfm).
+This software also allows you to set headers → for basic security with API_KEY.
+
+To quickly generate passwords or API keys I usually use this nifty website
+[RandomKeygen](https://randomkeygen.com/).
+
+Copy and paste code below over your previous code in file ```webapp.py```.
+
+```python
+# -*- coding: utf-8 -*-
+
+import time
+import bottle
+import random
+import dataset
+
+# initializing bottle app
+app = bottle.Bottle()
+
+# connects to sqlite database
+# check_same_thread=False allows using it in multi-threaded mode
+app.config["dsn"] = dataset.connect("sqlite:///data.db?check_same_thread=False")
+
+# api key that will be used in Arduino code
+app.config["api_key"] = "JtF2aUE5SGHfVJBCG5SH"
+
+# triggered when /api is accessed from browser
+# only accepts POST → no GET allowed
+@app.route("/api", method=["POST"])
+def route_default():
+  status = 400
+  ts = int(time.time()) # current timestamp
+  value = bottle.request.body.read() # data from device
+  api_key = bottle.request.get_header("Api_Key") # api key from header
+
+  # outputs to console received data for debug reason
+  print ">>> {} :: {}".format(value, api_key)
+
+  # if api_key is correct and value is present
+  # then writes attribute to point table
+  if api_key == app.config["api_key"] and value:
+    app.config["dsn"]["point"].insert(dict(ts=ts, value=value))
+    status = 200
+
+  # we only need to return status
+  return bottle.HTTPResponse(status=status, body="")
+
+# starting server on http://0.0.0.0:5000
+if __name__ == "__main__":
+  bottle.run(
+    app = app,
+    host = "0.0.0.0",
+    port = 5000,
+    debug = True,
+    reloader = True,
+    catchall = True,
+  )
+```
+
+To run this simply go to folder containing python file and run ```python
+webapp.py``` from terminal. If everything goes ok you should have simple API
+available via POST method on /api route.
+
+After testing the service with Restlet Client you should be able to view your
+data in a database file ```data.db```.
+
+![REST settings example](/assets/posts/iot-application/iot-rest-example.png){:loading="lazy"}
+
+You can also check the contents of new database file by using desktop client 
+for SQLite → [DB Browser for SQLite](http://sqlitebrowser.org/).
+
+![SQLite database example](/assets/posts/iot-application/iot-sqlite-db.png){:loading="lazy"}
+
+Table structure is as simple as it can be. We have ts (timestamp) and value
+(value from Arduino). As you can see timestamp is generated on API side. If you
+would happen to have atomic clock on Arduino it would be then better to generate
+and send timestamp with the value. This would be particularity useful if we
+would be collecting sensor data at a higher frequency and then sending this data
+in bulk to API.
+
+If you will deploy this app with uWSGI and multi-threaded, use DSN (Data Source
+Name) url with ```?check_same_thread=False```.
+
+Ok, now that we have some sort of a working API with some basic security so
+unwanted people can not post data to your database can we proceed further and
+try to program Arduino to send data to API.
+
+## Sending data to API with Arduino MKR1000
+
+First of all you should have MKR1000 module and microUSB cable to proceed.  If
+you have ever done any work with Arduino you should know that you also need
+[Arduino IDE](https://www.arduino.cc/en/Main/Software). On provided link you
+should be able to download and install IDE. Once that task is completed and you
+have successfully run blink example you should proceed to the next step.
+
+In order to use wireless capabilities of MKR1000 you need to first install
+[WiFi101 library](https://www.arduino.cc/en/Reference/WiFi101) in Arduino IDE.
+Please check before you install, you may already have it installed.
+
+Code below is a working example that sends data to API. Before you try to test
+your code make sure you have run Python web application. Then change settings
+for wifi, api endpoint and api_key. If by some reason code bellow doesn't work
+for you please leave a comment and I'll try to help.
+
+Once you have opened IDE and copied this code try to compile and upload it.
+Then open "Serial monitor" to see if any output is presented by Arduino.
+
+```c
+#include <WiFi101.h>
+
+// wifi settings
+char ssid[] = "ssid-name";
+char pass[] = "ssid-password";
+
+// api server enpoint
+char server[] = "192.168.6.22";
+int port = 5000;
+
+// api key that must be the same as the one in Python code
+String api_key = "JtF2aUE5SGHfVJBCG5SH";
+
+// frequency data is sent in ms - every 5 seconds
+int timeout = 1000 * 5;
+
+int status = WL_IDLE_STATUS;
+
+void setup() {
+
+  // initialize serial and wait for port to open:
+  Serial.begin(9600);
+  delay(1000);
+
+  // check for the presence of the shield
+  if (WiFi.status() == WL_NO_SHIELD) {
+    Serial.println("WiFi shield not present");
+    while (true);
+  }
+
+  // attempt to connect to wifi network
+  while (status != WL_CONNECTED) {
+    Serial.print("Attempting to connect to SSID: ");
+    Serial.println(ssid);
+    status = WiFi.begin(ssid, pass);
+    // wait 10 seconds for connection
+    delay(10000);
+  }
+
+  // output wifi status to serial monitor
+  Serial.print("SSID: ");
+  Serial.println(WiFi.SSID());
+
+  IPAddress ip = WiFi.localIP();
+  Serial.print("IP Address: ");
+  Serial.println(ip);
+
+  long rssi = WiFi.RSSI();
+  Serial.print("signal strength (RSSI):");
+  Serial.print(rssi);
+  Serial.println(" dBm");
+}
+
+void loop() {
+  WiFiClient client;
+
+  if (client.connect(server, port)) {
+
+    // I use random number generator for this example
+    // but you can use analog or digital inputs from arduino
+    String content = String(random(1000));
+
+    client.println("POST /api HTTP/1.1");
+    client.println("Connection: close");
+    client.println("Api-Key: " + api_key);
+    client.println("Content-Length: " + String(content.length()));
+    client.println();
+    client.println(content);
+
+    delay(100);
+    client.stop();
+    Serial.println("Data sent successfully ...");
+
+  } else {
+    Serial.println("Problem sending data ...");
+  }
+
+  // waits for x seconds and continue looping
+  delay(timeout);
+}
+```
+
+As seen from example you can notice that Arduino is generating random integer
+between [ 0 .. 1000 ]. You can easily replace this with a temperature sensor or
+any other kind of sensor.
+
+Now that we have API under the hood and Arduino is sending demo data we can now
+focus on data visualization.
+
+## Data visualization
+
+Before we continue we should examine our project folder structure. Currently we
+only have two files in our project:
+
+_simple-iot-app/_
+
+* _webapp.py_
+* _data.db_
+
+We will now add HTML template that will contain CSS and JavaScript code inline
+for the simplicity reason. And for the bottle framework to be able to scan root
+application folder for templates we will add ```bottle.TEMPLATE_PATH.insert(0,
+"./")``` in ```webapp.py```. By default bottle framework uses ```views/```
+subfolder to store templates. This is not the ideal situation and if you will
+use bottle to develop web applications you should use native behavior and store
+templates in it's predefined folder. But for the sake of example we will
+over-ride this. Be careful to fully replace your code with new code that is
+provided below. Avoid partially replacing code in file :) Also new code for
+reading data-points is provided in Python example below.
+
+First we add new route to our web application. It should be trigger when browser
+hits root of application ```http://0.0.0.0:5000/```. This route will do nothing
+more than render ```frontend.html``` template. This is done by ```return
+bottle.template("frontend.html")```. Check code below to further examine how
+exactly this is done.
+
+Now we will expand ```/api``` route and use different methods to write or read
+data-points. For writing data-point we will use POST method and for reading
+points we will use GET method. GET method will return JSON object with latest
+readings and historical data.
+
+There is a fantastic JavaScript library for plotting time-series charts called
+[MetricsGraphics.js](https://www.metricsgraphicsjs.org) that is based on
+[D3.js](https://d3js.org/) library for visualizing data.
+
+Data schema required by MetricsGraphics.js → to achieve this we need to
+transform data from database into this format:
+
+```json
+[
+  {
+    "date": "2017-08-11 01:07:20",
+    "value": 933
+  },
+  {
+    "date": "2017-08-11 01:07:30",
+    "value": 743
+  }
+]
+```
+
+Web application is now complete and we only need ```frontend.html``` that we
+will develop now. If you would try to start web app now and go to root app this
+will return error because we don't have frontend.html yet.
+
+```python
+# -*- coding: utf-8 -*-
+
+import time
+import bottle
+import json
+import datetime
+import random
+import dataset
+
+# initializing bottle app
+app = bottle.Bottle()
+
+# adds root directory as template folder
+bottle.TEMPLATE_PATH.insert(0, "./")
+
+# connects to sqlite database
+# check_same_thread=False allows using it in multi-threaded mode
+app.config["db"] = dataset.connect("sqlite:///data.db?check_same_thread=False")
+
+# api key that will be used in Arduino code
+app.config["api_key"] = "JtF2aUE5SGHfVJBCG5SH"
+
+# triggered when / is accessed from browser
+# only accepts GET → no POST allowed
+@app.route("/", method=["GET"])
+def route_default():
+  return bottle.template("frontend.html")
+
+# triggered when /api is accessed from browser
+# accepts POST and GET
+@app.route("/api", method=["GET", "POST"])
+def route_default():
+
+  # if method is POST then we write datapoint
+  if bottle.request.method == "POST":
+    status = 400
+    ts = int(time.time()) # current timestamp
+    value = bottle.request.body.read() # data from device
+    api_key = bottle.request.get_header("Api-Key") # api key from header
+
+    # outputs to console recieved data for debug reason
+    print ">>> {} :: {}".format(value, api_key)
+
+    # if api_key is correct and value is present
+    # then writes attribute to point table
+    if api_key == app.config["api_key"] and value:
+      app.config["db"]["point"].insert(dict(ts=ts, value=value))
+      status = 200
+
+      # we only need to return status
+      return bottle.HTTPResponse(status=status, body="")
+
+  # if method is GET then we read datapoint
+  else:
+    response = []
+    datapoints = app.config["db"]["point"].all()
+
+    for point in datapoints:
+      response.append({
+        "date": datetime.datetime.fromtimestamp(int(point["ts"])).strftime("%Y-%m-%d %H:%M:%S"),
+        "value": point["value"]
+      })
+
+    bottle.response.content_type = "application/json"
+    return json.dumps(response)
+
+# starting server on http://0.0.0.0:5000
+if __name__ == "__main__":
+  bottle.run(
+    app = app,
+    host = "0.0.0.0",
+    port = 5000,
+    debug = True,
+    reloader = True,
+    catchall = True,
+  )
+```
+
+And now finally we can implement ```frontend.html```. Create file with this name
+and copy code below. When you are done you can start web application.  Steps for
+this part are listed below the code.
+
+```html
+<!DOCTYPE html>
+<html>
+
+  <head>
+    <meta charset="utf-8">
+    <title>Simple IOT application</title>
+  </head>
+
+  <body>
+
+    <h1>Simple IOT application</h1>
+
+    <div class="chart-placeholder">
+      <div id="chart"></div>
+    </div>
+
+    <!-- application main script -->
+    <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
+    <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/4.10.0/d3.min.js"></script>
+    <script src="https://cdnjs.cloudflare.com/ajax/libs/metrics-graphics/2.11.0/metricsgraphics.min.js"></script>
+    <script>
+      function fetch_and_render() {
+        d3.json("/api", function(data) {
+          data = MG.convert.date(data, "date", "%Y-%m-%d %H:%M:%S");
+          MG.data_graphic({
+            data: data,
+            chart_type: "line",
+            full_width: true,
+            height: 270,
+            target: document.getElementById("chart"),
+            x_accessor: "date",
+            y_accessor: "value"
+          });
+        });
+      }
+      window.onload = function() {
+        // initial call for rendering
+        fetch_and_render();
+
+        // updates chart every 5 seconds
+        setInterval(function() {
+          fetch_and_render();
+        }, 5000);
+      }
+    </script>
+
+    <!-- application styles -->
+    <style>
+      body {
+        font: 13px sans-serif;
+        padding: 20px 50px;
+      }
+      .chart-placeholder {
+        border: 2px solid #ccc;
+        width: 100%;
+        user-select: none;
+      }
+      /* chart styles */
+      .mg-line1-color {
+        stroke: red;
+        stroke-width: 2;
+      }
+      .mg-main-area, .mg-main-line {
+        fill: #fff;
+      }
+      .mg-x-axis line, .mg-y-axis line {
+        stroke: #b3b2b2;
+        stroke-width: 1px;
+      }
+    </style>
+
+  </body>
+
+</html>
+```
+
+Now the folder structure should look like:
+
+_simple-iot-app/_
+
+* _webapp.py_
+* _data.db_
+* _frontend.html_
+
+Ok, lets now start application and start feeding it data.
+
+1. ```python webapp.py```
+2. connect Arduino MKR1000 to power source
+3. open browser and go to ```http://0.0.0.0:5000```
+
+If everything goes well you should be seeing new data-points rendered on chart
+every 5 seconds.
+
+If you navigate to ```http://0.0.0.0:5000``` you should see rendered chart as
+shown on picture below.
+
+![Application output](/assets/posts/iot-application/iot-app-output.png){:loading="lazy"}
+
+Complete application with all the code is available for
+[download](/assets/posts/iot-application/simple-iot-application.zip).
+
+## Conclusion
+
+I hope this clarifies some aspects of IOT application development. Of course
+this is a minimal example and is far from what can be done in real life with
+some further dive into other technologies.
+
+If you would like to continue exploring IOT world here are some interesting
+resources for you to examine:
+
+* [Reading Sensors with an Arduino](https://www.allaboutcircuits.com/projects/reading-sensors-with-an-arduino/)
+* [MQTT 101 – How to Get Started with the lightweight IoT Protocol](http://www.hivemq.com/blog/how-to-get-started-with-mqtt)
+* [Stream Updates with Server-Sent Events](https://www.html5rocks.com/en/tutorials/eventsource/basics/)
+* [Internet of Things (IoT) Tutorials](http://www.tutorialspoint.com/internet_of_things/)
+
+Any comment or additional ideas are welcomed in comments below.
diff --git a/_posts/posts/2018-01-16-using-digitalocean-spaces-object-storage-with-fuse.md b/_posts/posts/2018-01-16-using-digitalocean-spaces-object-storage-with-fuse.md
new file mode 100644
index 0000000..d29bd09
--- /dev/null
+++ b/_posts/posts/2018-01-16-using-digitalocean-spaces-object-storage-with-fuse.md
@@ -0,0 +1,332 @@
+---
+title: Using DigitalOcean Spaces Object Storage with FUSE
+permalink: /using-digitalocean-spaces-object-storage-with-fuse.html
+date: 2018-01-16T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+Couple of months ago [DigitalOcean](https://www.digitalocean.com) introduced new
+product called
+[Spaces](https://blog.digitalocean.com/introducing-spaces-object-storage/) which
+is Object Storage very similar to Amazon's S3. This really peaked my interest,
+because this was something I was missing and even the thought of going over the
+internet for such functionality was in no interest to me. Also in fashion with
+their previous pricing this also is very cheap and pricing page is a no-brainer
+compared to AWS or GCE. [Prices are clearly and precisely defined and
+outlined](https://www.digitalocean.com/pricing/).  You must love them for that
+:)
+
+## Initial requirements
+
+* Is it possible to use them as a mounted drive with FUSE? (tl;dr YES)
+* Will the performance degrade over time and over different sizes of objects?
+  (tl;dr NO&YES)
+* Can storage be mounted on multiple machines at the same time and be writable?
+  (tl;dr YES)
+
+> Let me be clear. This scripts I use are made just for benchmarking and are not
+> intended to be used in real-life situations. Besides that, I am looking into
+> using this approaches but adding caching service in front of it and then
+> dumping everything as an object to storage. This could potentially be some
+> interesting post of itself. But in case you would need real-time data without
+> eventual consistency please take this scripts as they are: not usable in such
+> situations.
+
+## Is it possible to use them as a mounted drive with FUSE?
+
+Well, actually they can be used in such manor. Because they are similar to [AWS
+S3](https://aws.amazon.com/s3/) many tools are available and you can find many
+articles and [Stackoverflow items](https://stackoverflow.com/search?q=s3+fuse).
+
+To make this work you will need DigitalOcean account. If you don't have one you
+will not be able to test this code. But if you have an account then you go and
+[create new
+Droplet](https://cloud.digitalocean.com/droplets/new?size=s-1vcpu-1gb&region=ams3&distro=debian&distroImage=debian-9-x64&options=private_networking,install_agent).
+If you click on this link you will already have preselected Debian 9 with
+smallest VM option.
+
+* Please be sure to add you SSH key, because we will login to this machine
+  remotely.
+* If you change your region please remember which one you choose because we will
+  need this information when we try to mount space to our machine.
+
+Instuctions on how to use SSH keys and how to setup them are available in
+article [How To Use SSH Keys with DigitalOcean
+Droplets](https://www.digitalocean.com/community/tutorials/how-to-use-ssh-keys-with-digitalocean-droplets).
+
+![DigitalOcean Droplets](/assets/posts/do-fuse/fuse-droplets.png){:loading="lazy"}
+
+After we created Droplet it's time to create new Space. This is done by clicking
+on a button [Create](https://cloud.digitalocean.com/spaces/new) (right top
+corner) and selecting Spaces. Choose pronounceable ```Unique name``` because we
+will use it in examples below. You can either choose Private or Public, it
+doesn't matter in our case. And you can always change that in the future.
+
+When you have created new Space we should [generate Access
+key](https://cloud.digitalocean.com/settings/api/tokens).  This link will guide
+to the page when you can generate this key. After you create new one, please
+save provided Key and Secret because Secret will not be shown again.
+
+![DigitalOcean Spaces](/assets/posts/do-fuse/fuse-spaces.png){:loading="lazy"}
+
+Now that we have new Space and Access key we should SSH into our machine.
+
+```bash
+# replace IP with the ip of your newly created droplet
+ssh root@IP
+
+# this will install utilities for mounting storage objects as FUSE
+apt install s3fs
+
+# we now need to provide credentials (access key we created earlier)
+# replace KEY and SECRET with your own credentials but leave the colon between them
+# we also need to set proper permissions
+echo "KEY:SECRET" > .passwd-s3fs
+chmod 600 .passwd-s3fs
+
+# now we mount space to our machine
+# replace UNIQUE-NAME with the name you choose earlier
+# if you choose different region for your space be careful about -ourl option (ams3)
+s3fs UNIQUE-NAME /mnt/ -ourl=https://ams3.digitaloceanspaces.com -ouse_cache=/tmp
+
+# now we try to create a file
+# once you mount it may take a couple of seconds to retrieve data
+echo "Hello cruel world" > /mnt/hello.txt
+```
+
+After all this you can return to your browser and go to [DigitalOcean
+Spaces](https://cloud.digitalocean.com/spaces) and click on your created
+space. If file hello.txt is present you have successfully mounted space to your
+machine and wrote data to it.
+
+I choose the same region for my Droplet and my Space but you don't have to.  You
+can have different regions. What this actually does to performance I don't know.
+
+Additional information on FUSE:
+
+* [Github project page for s3fs](https://github.com/s3fs-fuse/s3fs-fuse)
+* [FUSE - Filesystem in Userspace](https://en.wikipedia.org/wiki/Filesystem_in_Userspace)
+
+## Will the performance degrade over time and over different sizes of objects?
+
+For this task I didn't want to just read and write text files or uploading
+images. I actually wanted to figure out if using something like SQlite is viable
+in this case.
+
+### Measurement experiment 1: File copy
+
+```bash
+# first we create some dummy files at different sizes
+dd if=/dev/zero of=10KB.dat bs=1024 count=10 #10KB
+dd if=/dev/zero of=100KB.dat bs=1024 count=100 #100KB
+dd if=/dev/zero of=1MB.dat bs=1024 count=1024 #1MB
+dd if=/dev/zero of=10MB.dat bs=1024 count=10240 #10MB
+
+# now we set time command to only return real
+TIMEFORMAT=%R
+
+# now lets test it
+(time cp 10KB.dat /mnt/) |& tee -a 10KB.results.txt
+
+# and now we automate
+# this will perform the same operation 100 times
+# this will output results into separated files based on objecty size
+n=0; while (( n++ < 100 )); do (time cp 10KB.dat /mnt/10KB.$n.dat) |& tee -a 10KB.results.txt; done
+n=0; while (( n++ < 100 )); do (time cp 100KB.dat /mnt/100KB.$n.dat) |& tee -a 100KB.results.txt; done
+n=0; while (( n++ < 100 )); do (time cp 1MB.dat /mnt/1MB.$n.dat) |& tee -a 1MB.results.txt; done
+n=0; while (( n++ < 100 )); do (time cp 10MB.dat /mnt/10MB.$n.dat) |& tee -a 10MB.results.txt; done
+```
+
+Files of size 100MB were not successfully transferred and ended up displaying
+error (cp: failed to close '/mnt/100MB.1.dat': Operation not permitted).
+
+As I suspected, object size is not really that important. Sadly I don't have the
+time to test performance over periods of time. But if some of you would do it
+please send me your data. I would be interested in seeing results.
+
+**Here are plotted results**
+
+You can download [raw result here](/assets/posts/do-fuse/copy-benchmarks.tsv). 
+Measurements are in seconds.
+
+<script src="//cdn.plot.ly/plotly-latest.min.js"></script>
+<div id="copy-benchmarks"></div>
+<script>
+(function(){
+        var request = new XMLHttpRequest();
+        request.open("GET", "/assets/posts/do-fuse/copy-benchmarks.tsv", true);
+        request.onload = function() {
+                if (request.status >= 200 && request.status < 400) {
+                        var payload = request.responseText.trim();
+                        var tsv = payload.split("\n");
+                        for (var i=0; i<tsv.length; i++) { tsv[i] = tsv[i].split("\t"); }
+                        var traces = [];
+                        var headers = tsv[0];
+                        tsv.shift();
+                        Array.prototype.forEach.call(headers, function(el, idx) {
+                                var x = [];
+                                var y = [];
+                                for (var j=0; j<tsv.length; j++) {
+                                        x.push(j);
+                                        y.push(parseFloat(tsv[j][idx].replace(",", ".")));
+                                }
+                                traces.push({ x: x, y: y, type: "scatter", name: el, line: { width: 1, shape: "spline" } });
+                        });
+                        var copy = Plotly.newPlot("copy-benchmarks", traces, { legend: {"orientation": "h"}, height: 400, margin: { l: 40, r: 0, b: 20, t: 30, pad: 0 }, yaxis: { title: "execution time in seconds", titlefont: { size: 12 } }, xaxis: { title: "fn(i)", titlefont: { size: 12 } } });
+                } else { }
+        };
+        request.onerror = function() { };
+        request.send(null);
+})();
+</script>
+
+As far as these tests show, performance is quite stable and can be predicted
+which is fantastic. But this is a small test and spans only over couple of
+hours. So you should not completely trust them.
+
+### Measurement experiment 2: SQLite performanse
+
+I was unable to use database file directly from mounted drive so this is a no-go
+as I suspected. So I executed code below on a local disk just to get some
+benchmarks. I inserted 1000 records with DROPTABLE, CREATETABLE, INSERTMANY,
+FETCHALL, COMMIT for 1000 times to generate statistics. As you can see
+performance of SQLite is quite amazing. You could then potentially just copy
+file to mounted drive and be done with it.
+
+```python
+import time
+import sqlite3
+import sys
+
+if len(sys.argv) < 3:
+  print("usage: python sqlite-benchmark.py DB_PATH NUM_RECORDS REPEAT")
+  exit()
+
+def data_iter(x):
+  for i in range(x):
+    yield "m" + str(i), "f" + str(i*i)
+
+header_line = "%s\t%s\t%s\t%s\t%s\n" % ("DROPTABLE", "CREATETABLE", "INSERTMANY", "FETCHALL", "COMMIT")
+with open("sqlite-benchmarks.tsv", "w") as fp:
+  fp.write(header_line)
+
+start_time = time.time()
+conn = sqlite3.connect(sys.argv[1])
+c = conn.cursor()
+end_time = time.time()
+result_time = CONNECT = end_time - start_time
+print("CONNECT: %g seconds" % (result_time))
+
+start_time = time.time()
+c.execute("PRAGMA journal_mode=WAL")
+c.execute("PRAGMA temp_store=MEMORY")
+c.execute("PRAGMA synchronous=OFF")
+result_time = PRAGMA = end_time - start_time
+print("PRAGMA: %g seconds" % (result_time))
+
+for i in range(int(sys.argv[3])):
+  print("#%i" % (i))
+
+  start_time = time.time()
+  c.execute("drop table if exists test")
+  end_time = time.time()
+  result_time = DROPTABLE = end_time - start_time
+  print("DROPTABLE: %g seconds" % (result_time))
+
+  start_time = time.time()
+  c.execute("create table if not exists test(a,b)")
+  end_time = time.time()
+  result_time = CREATETABLE = end_time - start_time
+  print("CREATETABLE: %g seconds" % (result_time))
+
+  start_time = time.time()
+  c.executemany("INSERT INTO test VALUES (?, ?)", data_iter(int(sys.argv[2])))
+  end_time = time.time()
+  result_time = INSERTMANY = end_time - start_time
+  print("INSERTMANY: %g seconds" % (result_time))
+
+  start_time = time.time()
+  c.execute("select count(*) from test")
+  res = c.fetchall()
+  end_time = time.time()
+  result_time = FETCHALL = end_time - start_time
+  print("FETCHALL: %g seconds" % (result_time))
+
+  start_time = time.time()
+  conn.commit()
+  end_time = time.time()
+  result_time = COMMIT = end_time - start_time
+  print("COMMIT: %g seconds" % (result_time))
+
+  print
+  log_line = "%f\t%f\t%f\t%f\t%f\n" % (DROPTABLE, CREATETABLE, INSERTMANY, FETCHALL, COMMIT)
+  with open("sqlite-benchmarks.tsv", "a") as fp:
+    fp.write(log_line)
+
+start_time = time.time()
+conn.close()
+end_time = time.time()
+result_time = CLOSE = end_time - start_time
+print("CLOSE: %g seconds" % (result_time))
+```
+
+You can download [raw result here](/assets/posts/do-fuse/sqlite-benchmarks.tsv). And 
+again, these results are done on a local block storage and do not represent 
+capabilities of object storage. With my current approach and state of the test 
+code these can not be done. I would need to make Python code much more robust 
+and check locking etc.
+
+<div id="sqlite-benchmarks"></div>
+<script>
+(function(){
+        var request = new XMLHttpRequest();
+        request.open("GET", "/assets/posts/do-fuse/sqlite-benchmarks.tsv", true);
+        request.onload = function() {
+                if (request.status >= 200 && request.status < 400) {
+                        var payload = request.responseText.trim();
+                        var tsv = payload.split("\n");
+                        for (var i=0; i<tsv.length; i++) { tsv[i] = tsv[i].split("\t"); }
+                        var traces = [];
+                        var headers = tsv[0];
+                        tsv.shift();
+                        Array.prototype.forEach.call(headers, function(el, idx) {
+                                var x = [];
+                                var y = [];
+                                for (var j=0; j<tsv.length; j++) {
+                                        x.push(j);
+                                        y.push(parseFloat(tsv[j][idx].replace(",", ".")));
+                                }
+                                traces.push({ x: x, y: y, type: "scatter", name: el, line: { width: 1, shape: "spline" } });
+                        });
+                        var sqlite = Plotly.newPlot("sqlite-benchmarks", traces, { legend: {"orientation": "h"}, height: 400, margin: { l: 50, r: 0, b: 20, t: 30, pad: 0 }, yaxis: { title: "execution time in seconds", titlefont: { size: 12 } } });
+                } else { }
+        };
+        request.onerror = function() { };
+        request.send(null);
+})();
+</script>
+
+## Can storage be mounted on multiple machines at the same time and be writable?
+
+Well, this one didn't take long to test. And the answer is **YES**. I mounted
+space on both machines and measured same performance on both machines. But
+because file is downloaded before write and then uploaded on complete there
+could potentially be problems is another process is trying to access the same
+file.
+
+## Observations and conslusion
+
+Using Spaces in this way makes it easier to access and manage files. But besides
+that you would need to write additional code to make this one play nice with you
+applications.
+
+Nevertheless, this was extremely simple to setup and use and this is just
+another excellent product in DigitalOcean product line. I found this exercise
+very valuable and am thinking about implementing some sort of mechanism for
+SQLite, so data can be stored on Spaces and accessed by many VM's. For a project
+where data doesn't need to be accessible in real-time and can have couple of
+minutes old data this would be very interesting. If any of you find this
+proposal interesting please write in a comment box below or shoot me an email
+and I will keep you posted.
diff --git a/_posts/posts/2019-01-03-encoding-binary-data-into-dna-sequence.md b/_posts/posts/2019-01-03-encoding-binary-data-into-dna-sequence.md
new file mode 100644
index 0000000..6980ed1
--- /dev/null
+++ b/_posts/posts/2019-01-03-encoding-binary-data-into-dna-sequence.md
@@ -0,0 +1,416 @@
+---
+title: Encoding binary data into DNA sequence
+permalink: /encoding-binary-data-into-dna-sequence.html
+date: 2019-01-03T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Initial thoughts
+
+Imagine a world where you could go outside and take a leaf from a tree and put
+it through your personal DNA sequencer and get data like music, videos or
+computer programs from it. Well, this is all possible now. It was not done on a
+large scale because it is quite expensive to create DNA strands but it's
+possible.
+
+Encoding data into DNA sequence is relatively simple process once you understand
+the relationship between binary data and nucleotides and scientists have been
+making large leaps in this field in order to provide viable long-term storage
+solution for our data that would potentially survive our specie if case of
+global disaster. We could imprint all the world's knowledge into plants and
+ensure the survival of our knowledge.
+
+More optimistic usage for this technology would be easier storage of ever
+growing data we produce every day. Once machines for sequencing DNA become fast
+enough and cheaper this could mean the next evolution of storing data and
+abandoning classical hard and solid state drives in data warehouses.
+
+As we currently stand this is still not viable but it is quite an amazing and
+cool technology.
+
+My interests in this field are purely in encoding processes and experimental
+testing mainly because I don't have the access to this expensive machines. My
+initial goal was to create a toolkit that can be used by everybody to encode
+their data into a proper DNA sequence.
+
+## Glossary
+
+**deoxyribose** A five-carbon sugar molecule with a hydrogen atom rather than a
+hydroxyl group in the 2′ position; the sugar component of DNA nucleotides.
+
+**double helix** The molecular shape of DNA in which two strands of nucleotides
+wind around each other in a spiral shape.
+
+**nitrogenous base** A nitrogen-containing molecule that acts as a base; often
+referring to one of the purine or pyrimidine components of nucleic acids.
+
+**phosphate group** A molecular group consisting of a central phosphorus atom
+bound to four oxygen atoms.
+
+**RGB** The RGB color model is an additive color model in which red, green and
+blue light are added together in various ways to reproduce a broad array of
+colors.
+
+**GCC** The GNU Compiler Collection is a compiler system produced by the GNU
+Project supporting various programming languages.
+
+## Data encoding
+
+**TL;DR:** Encoding involves the use of a code to change original data into a
+form that can be used by an external process.
+
+Encoding is the process of converting data into a format required for a number
+of information processing needs, including:
+
+- Program compiling and execution
+- Data transmission, storage and compression/decompression
+- Application data processing, such as file conversion
+
+Encoding can have two meanings:
+
+- In computer technology, encoding is the process of applying a specific code,
+  such as letters, symbols and numbers, to data for conversion into an
+  equivalent cipher.
+- In electronics, encoding refers to analog to digital conversion.
+
+## Quick history of DNA
+
+- **1869** - Friedrich Miescher identifies "nuclein".
+- **1900s** - The Eugenics Movement.
+- **1900** – Mendel's theories are rediscovered by researchers.
+- **1944** - Oswald Avery identifies DNA as the 'transforming principle'.
+- **1952** - Rosalind Franklin photographs crystallized DNA fibres.
+- **1953** - James Watson and Francis Crick discover the double helix structure of DNA.
+- **1965** - Marshall Nirenberg is the first person to sequence the bases in each codon.
+- **1983** - Huntington's disease is the first mapped genetic disease.
+- **1990** - The Human Genome Project begins.
+- **1995** - Haemophilus Influenzae is the first bacterium genome sequenced.
+- **1996** - Dolly the sheep is cloned.
+- **1999** - First human chromosome is decoded.
+- **2000** – Genetic code of the fruit fly is decoded.
+- **2002** – Mouse is the first mammal to have its genome decoded.
+- **2003** – The Human Genome Project is completed.
+- **2013** – DNA Worldwide and Eurofins Forensic discover identical twins have differences in their genetic makeup.
+
+## What is DNA?
+
+Deoxyribonucleic acid, a self-replicating material which is **present in nearly
+all living organisms** as the main constituent of chromosomes. It is the
+**carrier of genetic information**.
+
+> The nitrogen in our DNA, the calcium in our teeth, the iron in our blood,
+> the carbon in our apple pies were made in the interiors of collapsing stars.
+> We are made of starstuff.
+> **-- Carl Sagan, Cosmos**
+
+The nucleotide in DNA consists of a sugar (deoxyribose), one of four bases
+(cytosine (C), thymine (T), adenine (A), guanine (G)), and a phosphate.
+Cytosine and thymine are pyrimidine bases, while adenine and guanine are purine
+bases. The sugar and the base together are called a nucleoside.
+
+![DNA](/assets/posts/dna-sequence/dna-basics.jpg){:loading="lazy"}
+
+*DNA (a) forms a double stranded helix, and (b) adenine pairs with thymine and
+cytosine pairs with guanine. (credit a: modification of work by Jerome Walker,
+Dennis Myts)*
+
+## Encode binary data into DNA sequence
+
+As an input file you can use any file you want:
+
+- ASCII files,
+- Compiled programs,
+- Multimedia files (MP3, MP4, MVK, etc),
+- Images,
+- Database files,
+- etc.
+
+Note: If you would copy all the bytes from RAM to file or pipe data to file you
+could encode also this data as long as you provide file pointer to the encoder.
+
+### Basic Encoding
+
+As already mentioned, the Basic Encoding is based on a simple mapping. Since DNA
+is composed of 4 nucleotides (Adenine, Cytosine, Guanine, Thymine; usually
+referred using the first letter). Using this technique we can encode
+
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+
+using a single nucleotide. In this way, we are able to use the 4 bases that
+compose the DNA strand to encode each byte of data.
+
+| Two bits | Nucleotides      |
+| -------- | ---------------- |
+| 00       | **A** (Adenine)  |
+| 10       | **G** (Guanine)  |
+| 01       | **C** (Cytosine) |
+| 11       | **T** (Thymine)  |
+
+With this in mind we can simply encode any data by using two-bit to Nucleotides
+conversion.
+
+```python
+{ Algorithm 1: Naive byte array to DNA encode }
+procedure EncodeToDNASequence(f) string
+begin
+  enc string
+  while not eof(f) do
+    c byte := buffer[0]                             { Read 1 byte from buffer }
+    bin integer := sprintf('08b', c)                { Convert to string binary }
+    for e in range[0, 2, 4, 6] do
+      if e[0] == 48 and e[1] == 48 then             { 0x00 - A (Adenine) }
+        enc += 'A'
+      else if e[0] == 48 and e[1] == 49 then        { 0x01 - G (Guanine) }
+        enc += 'G'
+      else if e[0] == 49 and e[1] == 48 then        { 0x10 - C (Cytosine) }
+        enc += 'C'
+      else if e[0] == 49 and e[1] == 49 then        { 0x11 - T (Thymine) }
+        enc += 'T'
+  return enc                                        { Return DNA sequence }
+end
+```
+
+Another encoding would be **Goldman encoding**. Using this encoding helps with
+Nonsense mutation (amino acids replaced by a stop codon) that occurs and is the
+most problematic during translation because it leads to truncated amino acid
+sequences, which in turn results in truncated proteins.
+
+[Where to store big data? In DNA: Nick Goldman at TEDxPrague](https://www.youtube.com/watch?v=a4PiGWNsIEU)
+
+### FASTA file format
+
+In bioinformatics, FASTA format is a text-based format for representing either
+nucleotide sequences or peptide sequences, in which nucleotides or amino acids
+are represented using single-letter codes. The format also allows for sequence
+names and comments to precede the sequences. The format originates from the
+FASTA software package, but has now become a standard in the field of
+bioinformatics.
+
+The first line in a FASTA file started either with a ">" (greater-than) symbol
+or, less frequently, a ";" (semicolon) was taken as a comment. Subsequent lines
+starting with a semicolon would be ignored by software. Since the only comment
+used was the first, it quickly became used to hold a summary description of the
+sequence, often starting with a unique library accession number, and with time
+it has become commonplace to always use ">" for the first line and to not use
+";" comments (which would otherwise be ignored).
+
+```txt
+;LCBO - Prolactin precursor - Bovine
+; a sample sequence in FASTA format
+MDSKGSSQKGSRLLLLLVVSNLLLCQGVVSTPVCPNGPGNCQVSLRDLFDRAVMVSHYIHDLSS
+EMFNEFDKRYAQGKGFITMALNSCHTSSLPTPEDKEQAQQTHHEVLMSLILGLLRSWNDPLYHL
+VTEVRGMKGAPDAILSRAIEIEEENKRLLEGMEMIFGQVIPGAKETEPYPVWSGLPSLQTKDED
+ARYSAFYNLLHCLRRDSSKIDTYLKLLNCRIIYNNNC*
+
+>MCHU - Calmodulin - Human, rabbit, bovine, rat, and chicken
+ADQLTEEQIAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTID
+FPEFLTMMARKMKDTDSEEEIREAFRVFDKDGNGYISAAELRHVMTNLGEKLTDEEVDEMIREA
+DIDGDGQVNYEEFVQMMTAK*
+
+>gi|5524211|gb|AAD44166.1| cytochrome b [Elephas maximus maximus]
+LCLYTHIGRNIYYGSYLYSETWNTGIMLLLITMATAFMGYVLPWGQMSFWGATVITNLFSAIPYIGTNLV
+EWIWGGFSVDKATLNRFFAFHFILPFTMVALAGVHLTFLHETGSNNPLGLTSDSDKIPFHPYYTIKDFLG
+LLILILLLLLLALLSPDMLGDPDNHMPADPLNTPLHIKPEWYFLFAYAILRSVPNKLGGVLALFLSIVIL
+GLMPFLHTSKHRSMMLRPLSQALFWTLTMDLLTLTWIGSQPVEYPYTIIGQMASILYFSIILAFLPIAGX
+IENY
+```
+
+FASTA format was extended by [FASTQ](https://en.wikipedia.org/wiki/FASTQ_format)
+format from the [Sanger Centre](https://www.sanger.ac.uk/) in Cambridge.
+
+### PNG encoded DNA sequence
+
+| Nucleotides  | RGB         | Color name |
+| ------------ | ----------- | ---------- |
+| A ➞ Adenine  | (0,0,255)   | Blue       |
+| G ➞ Guanine  | (0,100,0)   | Green      |
+| C ➞ Cytosine | (255,0,0)   | Red        |
+| T ➞ Thymine  | (255,255,0) | Yellow     |
+
+With this in mind we can create a simple algorithm to create PNG representation
+of a DNA sequence.
+
+```python
+{ Algorithm 2: Naive DNA to PNG encode from FASTA file }
+procedure EncodeDNASequenceToPNG(f)
+begin
+  i image
+  while not eof(f) do
+    c char := buffer[0]                             { Read 1 char from buffer }
+    case c of
+      'A': color := RGB(0, 0, 255)                  { Blue }
+      'G': color := RGB(0, 100, 0)                  { Green }
+      'C': color := RGB(255, 0, 0)                  { Red }
+      'T': color := RGB(255, 255, 0)                { Yellow }
+    drawRect(i, [x, y], color)
+  save(i)                                           { Save PNG image }
+end
+```
+
+## Encoding text file in practice
+
+In this example we will take a simple text file as our input stream for
+encoding. This file will have a quote from Niels Bohr and saved as txt file.
+
+> How wonderful that we have met with a paradox. Now we have some hope of
+> making progress.
+> ― Niels Bohr
+
+First we encode text file into FASTA file.
+
+```bash
+./dnae-encode -i quote.txt -o quote.fa
+2019/01/10 00:38:29 Gathering input file stats
+2019/01/10 00:38:29 Starting encoding ...
+ 106 B / 106 B [==================================] 100.00% 0s
+2019/01/10 00:38:29 Saving to FASTA file ...
+2019/01/10 00:38:29 Output FASTA file length is 438 B
+2019/01/10 00:38:29 Process took 987.263µs
+2019/01/10 00:38:29 Done ...
+```
+
+Output of `quote.fa` file contains the encoded DNA sequence in ASCII format.
+
+```txt
+>SEQ1
+GACAGCTTGTGTACAAGTGTGCTTGCTCGCGAGCGGGTACGCGCGTGGGCTAACAAGTGA
+GCCAGCAGGTGAACAAGTGTGCGGACAAGCCAGCAGGTGCGCGGACAAGCTGGCGGGTGA
+ACAAGTGTGCCGGTGAGCCAACAAGCAGACAAGTAAGCAGGTACGCAGGCGAGCTTGTCA
+ACTCACAAGATCGCTTGTGTACAAGTGTGCGGACAAGCCAGCAGGTGCGCGGACAAGTAT
+GCTTGCTGGCGGACAAGCCAGCTTGTAAGCGGACAAGCTTGCGCACAAGCTGGCAGGCCT
+GCCGGCTCGCGTACAAATTCACAAGTAAGTACGCTTGCGTGTACGCGGGTATGTATACTC
+AACCTCACCAAACGGGACAAGATCGCCGGCGGGCTAGTATACAAGAACGCTTGCCAGTAC
+AACC
+```
+
+Then we encode FASTA file from previous operation to encode this data into PNG.
+
+```bash
+./dnae-png -i quote.fa -o quote.png
+2019/01/10 00:40:09 Gathering input file stats ...
+2019/01/10 00:40:09 Deconstructing FASTA file ...
+2019/01/10 00:40:09 Compositing image file ...
+ 424 / 424 [==================================] 100.00% 0s
+2019/01/10 00:40:09 Saving output file ...
+2019/01/10 00:40:09 Output image file length is 1.1 kB
+2019/01/10 00:40:09 Process took 19.036117ms
+2019/01/10 00:40:09 Done ...
+```
+
+After encoding into PNG format this file looks like this.
+
+![Encoded Quote in PNG format](/assets/posts/dna-sequence/quote.png){:loading="lazy"}
+
+The larger the input stream is the larger the PNG file would be.
+
+Compiled basic Hello World C program with
+[GCC](https://www.gnu.org/software/gcc/) would [look
+like](/assets/posts/dna-sequence/sample.png).
+
+```c
+// gcc -O3 -o sample sample.c
+#include <stdio.h>
+
+main() {
+  printf("Hello, world!\n");
+  return 0;
+}
+```
+
+## Toolkit for encoding data
+
+I have created a toolkit with two main programs:
+
+- dnae-encode (encodes file into FASTA file)
+- dnae-png (encodes FASTA file into PNG)
+
+Toolkit with full source code is available on
+[github.com/mitjafelicijan/dna-encoding](https://github.com/mitjafelicijan/dna-encoding).
+
+### dnae-encode
+
+```bash
+> ./dnae-encode --help
+usage: dnae-encode --input=INPUT [<flags>]
+
+A command-line application that encodes file into DNA sequence.
+
+Flags:
+      --help             Show context-sensitive help (also try --help-long and --help-man).
+  -i, --input=INPUT      Input file (ASCII or binary) which will be encoded into DNA sequence.
+  -o, --output="out.fa"  Output file which stores DNA sequence in FASTA format.
+  -s, --sequence=SEQ1    The description line (defline) or header/identifier line, gives a name and/or a unique identifier for the sequence.
+  -c, --columns=60       Row characters length (no more than 120 characters). Devices preallocate fixed line sizes in software.
+      --version          Show application version.
+```
+
+### dnae-png
+
+```bash
+> ./dnae-png --help
+usage: dnae-png --input=INPUT [<flags>]
+
+A command-line application that encodes FASTA file into PNG image.
+
+Flags:
+      --help              Show context-sensitive help (also try --help-long and --help-man).
+  -i, --input=INPUT       Input FASTA file which will be encoded into PNG image.
+  -o, --output="out.png"  Output file in PNG format that represents DNA sequence in graphical way.
+  -s, --size=10           Size of pairings of DNA bases on image in pixels (lower resolution lower file size).
+      --version           Show application version.
+```
+
+## Benchmarks
+
+First we generate some binary sample data with dd.
+
+```bash
+dd if=<(openssl enc -aes-256-ctr  -pass pass:"$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64)" -nosalt < /dev/zero) of=1KB.bin bs=1KB count=1 iflag=fullblock
+```
+
+![Sample binary file 1KB](/assets/posts/dna-sequence/sample-binary-file.png){:loading="lazy"}
+
+Our freshly generated 1KB file looks something like this (its full of
+garbage data as intended).
+
+We create following binary files:
+
+- 1KB.bin
+- 10KB.bin
+- 100KB.bin
+- 1MB.bin
+- 10MB.bin
+- 100MB.bin
+
+After this we create FASTA files for all the binary files by encoding them
+into DNA sequence.
+
+```bash
+./dnae-encode -i 100MB.bin -o 100MB.fa
+```
+
+Then we GZIP all the FASTA files to see how much the can be compressed.
+
+```bash
+gzip -9 < 10MB.fa > 10MB.fa.gz
+```
+
+![Encode to FASTA](/assets/posts/dna-sequence/chart-speed.svg){:loading="lazy"}
+
+The speed increase that occurs when encoding to FASTA format.
+
+![File sizes](/assets/posts/dna-sequence/chart-size.svg){:loading="lazy"}
+
+Size of the out file after encoding.
+
+[Download CSV file with benchmarks](/assets/posts/dna-sequence/benchmarks.csv).
+
+## References
+
+- https://www.techopedia.com/definition/948/encoding
+- https://www.dna-worldwide.com/resource/160/history-dna-timeline
+- https://opentextbc.ca/biology/chapter/9-1-the-structure-of-dna/
+- https://arxiv.org/abs/1801.04774
+- https://en.wikipedia.org/wiki/FASTA_format
diff --git a/_posts/posts/2019-10-14-simplifying-and-reducing-clutter.md b/_posts/posts/2019-10-14-simplifying-and-reducing-clutter.md
new file mode 100644
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--- /dev/null
+++ b/_posts/posts/2019-10-14-simplifying-and-reducing-clutter.md
@@ -0,0 +1,60 @@
+---
+title: Simplifying and reducing clutter in my life and work
+permalink: /simplifying-and-reducing-clutter.html
+date: 2019-10-14T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+I recently moved my main working machine back from Hachintosh to Linux. Well the
+experiment was interesting and I have done some great work on macOS but it was
+time to move back.
+
+I actually really missed Linux. The simplicity of `apt-get` or just the amount
+of software that exists for Linux should be a no-brainer. I spent most of my
+time on macOS finding solutions to make things work. Using
+[Brew](https://brew.sh/) was just a horrible experience and far from package
+managers of Linux. At least they managed to get that `sudo` debacle sorted.
+
+Not all was bad. macOS in general was a perfectly good environment. Things like
+Docker and tooling like this worked without any hiccups. My normal tools like
+coding IDE worked flawlessly and the whole look and feel is just superb. I have
+been using MacBook Air for couple of years so I was used to the system but never
+as a daily driver.
+
+One of the things I did after I installed Linux back on my machine was cleaning
+up my Dropbox folder. I have everything on Dropbox. Even projects folder. I
+write code for living so my whole life revolves around couple of megs of code
+(with assets). So it's not like I have huge files on my machine. I don't have
+movies or music or pictures on my PC. All of that stuff is in cloud. I use
+Google music and I have Netflix account which is more than enough for me.
+
+I also went and deleted some of the repositories on my Github account. I have
+deleted more code than deployed. People find this strange but for me deleting
+something feels so cathartic and also forces me to write better code next time
+around when I am faced with similar problem. That was a huge relief if I am
+being totally honest.
+
+Next step was to do something with my webpage. I have been using some scripts I
+wrote a while ago to generate static pages from markdown source posts. I kept on
+adding and adding stuff on top of it and it became a source of a
+frustration. And this is just a simple blog and I was using gulp and npm.
+Anyways after couple of hours of searching and testing static generators I found
+an interesting one
+[https://github.com/piranha/gostatic](https://github.com/piranha/gostatic) and I
+just decided to use this one. It was the only one that had a simple templating
+engine, not that I really need one. But others had this convoluted way of trying
+to solve everything and at the end just required quite bigger learning curve I
+was ready to go with. So I deleted couple of old posts, simplified HTML, trashed
+most of the CSS and went with
+[https://motherfuckingwebsite.com/](https://motherfuckingwebsite.com/)
+aesthetics.  Yeah, the previous site was more visually stimulating but all I
+really care is the content at this point. And Times New Roman font is kind of
+awesome.
+
+I stopped working on most of the projects in the past couple of months because
+the overhead was just too insane. There comes a point when you stretch yourself
+too much and then you stop progressing and with that comes dissatisfaction.
+
+So that's about it. Moving forward minimal style.
diff --git a/_posts/posts/2019-10-19-using-sentiment-analysis-for-clickbait-detection.md b/_posts/posts/2019-10-19-using-sentiment-analysis-for-clickbait-detection.md
new file mode 100644
index 0000000..a1b237b
--- /dev/null
+++ b/_posts/posts/2019-10-19-using-sentiment-analysis-for-clickbait-detection.md
@@ -0,0 +1,109 @@
+---
+title: Using sentiment analysis for clickbait detection in RSS feeds
+permalink: /using-sentiment-analysis-for-clickbait-detection-in-rss-feeds.html
+date: 2019-10-19T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Initial thoughts
+
+One of the things that interested me for a while now is if major well
+established news sites use click bait titles to drive additional traffic to
+their sites and generate additional impressions.
+
+Goal is to see how article titles and actual content of article differ from each
+other and see if titles are clickbaited.
+
+## Preparing and cleaning data
+
+For this example I opted to just use RSS feed from a new website and decided to
+go with [The Guardian](https://www.theguardian.com) World news. While this gets
+us limited data (~40) articles and also description (actual content) is trimmed
+this really doesn't reflect the actual article contents.
+
+To get better content I could use web scraping and use RSS as link list and
+fetch contents directly from website, but for this simple example this will
+suffice.
+
+There are couple of requirements we need to install before we continue:
+
+- `pip3 install feedparser` (parses RSS feed from url)
+- `pip3 install vaderSentiment` (does sentiment polarity analysis)
+- `pip3 install matplotlib` (plots chart of results)
+
+So first we need to fetch RSS data and sanitize HTML content from description.
+
+```python
+import re
+import feedparser
+
+feed_url = "https://www.theguardian.com/world/rss"
+feed = feedparser.parse(feed_url)
+
+# sanitize html
+for item in feed.entries:
+    item.description = re.sub('<[^<]+?>', '', item.description)
+```
+
+## Perform sentiment analysis
+
+Since we now have cleaned up data in our `feed.entries` object we can start with
+performing sentiment analysis.
+
+There are many sentiment analysis libraries available that range from rule-based
+sentiment analysis up to machine learning supported analysis. To keep things
+simple I decided to use rule-based analysis library
+[vaderSentiment](https://github.com/cjhutto/vaderSentiment) from
+[C.J. Hutto](https://github.com/cjhutto). Really nice library and quite easy to
+use.
+
+```python
+from vaderSentiment.vaderSentiment import SentimentIntensityAnalyzer
+analyser = SentimentIntensityAnalyzer()
+
+sentiment_results = []
+for item in feed.entries:
+    sentiment_title = analyser.polarity_scores(item.title)
+    sentiment_description = analyser.polarity_scores(item.description)
+    sentiment_results.append([sentiment_title['compound'], sentiment_description['compound']])
+```
+
+Now that we have this data in a shape that is compatible with matplotlib we can
+plot results to see the difference between title and description sentiment of an
+article.
+
+```python
+import matplotlib.pyplot as plt
+
+plt.rcParams['figure.figsize'] = (15, 3)
+plt.plot(sentiment_results, drawstyle='steps')
+plt.title('Sentiment analysis relationship between title and description (Guardian World News)')
+plt.legend(['title', 'description'])
+plt.show()
+```
+
+## Results and assets
+
+1. Because of the small sample size further conclusions are impossible to make.
+2. Rule-based approach may not be the best way of doing this. By using deep
+   learning we would be able to get better insights.
+3. **Next step would be to** periodically fetch RSS items and store them over a
+   longer period of time and then perform analysis again and use either machine
+   learning or deep learning on top of it.
+
+![Relationship between title and description](/assets/posts/sentiment-analysis/guardian-sa-title-desc-relationship.png){:loading="lazy"}
+
+Figure above displays difference between title and description sentiment for
+specific RSS feed item. 1 means positive and -1 means negative sentiment.
+
+[» Download Jupyter Notebook](/assets/posts/sentiment-analysis/sentiment-analysis.ipynb)
+
+## Going further
+
+- [Twitter Sentiment Analysis by Bryan Schwierzke](https://github.com/bswiss/news_mood)
+- [AFINN-based sentiment analysis for Node.js by Andrew Sliwinski](https://github.com/thisandagain/sentiment)
+- [Sentiment Analysis with LSTMs in Tensorflow by Adit Deshpande](https://github.com/adeshpande3/LSTM-Sentiment-Analysis)
+- [Sentiment analysis on tweets using Naive Bayes, SVM, CNN, LSTM, etc. by Abdul Fatir](https://github.com/abdulfatir/twitter-sentiment-analysis)
+
diff --git a/_posts/posts/2020-03-22-simple-sse-based-pubsub-server.md b/_posts/posts/2020-03-22-simple-sse-based-pubsub-server.md
new file mode 100644
index 0000000..ffb7285
--- /dev/null
+++ b/_posts/posts/2020-03-22-simple-sse-based-pubsub-server.md
@@ -0,0 +1,455 @@
+---
+title: Simple Server-Sent Events based PubSub Server
+permalink: /simple-server-sent-events-based-pubsub-server.html
+date: 2020-03-22T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Before we continue ...
+
+Publisher Subscriber model is nothing new and there are many amazing solutions
+out there, so writing a new one would be a waste of time if other solutions
+wouldn't have quite complex install procedures and weren't so hard to maintain.
+But to be fair, comparing this simple server with something like
+[Kafka](https://kafka.apache.org/) or [RabbitMQ](https://www.rabbitmq.com/) is
+laughable at the least. Those solutions are enterprise grade and have many
+mechanisms there to ensure messages aren't lost and much more. Regardless of
+these drawbacks, this method has been tested on a large website and worked until
+now without any problems. So now, that we got that cleared up, let's continue.
+
+***Wiki definition:** Publish/subscribe messaging, or pub/sub messaging, is a
+form of asynchronous service-to-service communication used in serverless and
+microservices architectures. In a pub/sub model, any message published to a
+topic is immediately received by all the subscribers to the topic.*
+
+## General goals
+
+- provide a simple server that relays messages to all the connected clients,
+- messages can be posted on specific topics,
+- messages get sent via [Server-Sent
+  Events](https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events)
+  to all the subscribers.
+
+## How exactly does the pub/sub model work?
+
+The easiest way to explain this is with diagram bellow. Basic function is
+simple. We have subscribers that receive messages, and we have publishers that
+create and post messages. Similar model is also well know pattern that works on
+a premise of consumers and producers, and they take similar roles.
+
+![How PubSub works](/assets/posts/simple-pubsub-server/pubsub-overview.png){:loading="lazy"}
+
+**These are some naive characteristics we want to achieve:**
+
+- producer is publishing messages to subscribe topic,
+- consumer is receiving messages from subscribed topic,
+- servers is also known as Broker,
+- broker does not store messages or tracks success,
+- broker uses
+  [FIFO](https://en.wikipedia.org/wiki/FIFO_(computing_and_electronics)) method
+  for delivering messages,
+- if consumer wants to receive messages from a topic, producer and consumer
+  topics must match,
+- consumer can subscribe to multiple topics,
+- producer can publish to multiple topics,
+- each message has a messageId.
+
+**Known drawbacks:**
+
+- messages will not be stored in a persistent queue or unreceived messages like
+  [DeadLetterQueue](https://en.wikipedia.org/wiki/Dead_letter_queue) so old
+  messages could be lost on server restart,
+- [Server-Sent
+  Events](https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events)
+  opens a long-running connection between the client and the server so make sure
+  if your setup is load balanced that the load balancer in this case can have
+  long opened connection,
+- no system moderation due to the dynamic nature of creating queues.
+
+## Server-Sent Events
+
+Read more about it on [official specification
+page](https://html.spec.whatwg.org/multipage/server-sent-events.html).
+
+### Current browser support
+
+![Browser support](/assets/posts/simple-pubsub-server/caniuse.png){:loading="lazy"}
+
+Check
+[https://caniuse.com/#feat=eventsource](https://caniuse.com/#feat=eventsource)
+for latest information about browser support.
+
+### Known issues
+
+- Firefox 52 and below do not support EventSource in web/shared workers
+- In Firefox prior to version 36 server-sent events do not reconnect
+  automatically in case of a connection interrupt (bug)
+- Reportedly, CORS in EventSource is currently supported in Firefox 10+, Opera
+  12+, Chrome 26+, Safari 7.0+.
+- Antivirus software may block the event streaming data chunks.
+
+Source: [https://caniuse.com/#feat=eventsource](https://caniuse.com/#feat=eventsource)
+
+### Message format
+
+The simplest message that can be sent is only with data attribute:
+
+```bash
+data: this is a simple message
+<blank line>
+```
+
+You can send message IDs to be used if the connection is dropped:
+
+```bash
+id: 33
+data: this is line one
+data: this is line two
+<blank line>
+```
+
+And you can specify your own event types (the above messages will all trigger
+the message event):
+
+```bash
+id: 36
+event: price
+data: 103.34
+<blank line>
+```
+
+### Server requirements
+
+The important thing is how you send headers and which headers are sent by the
+server that triggers browser to threat response as a EventStream.
+
+Headers responsible for this are:
+
+```bash
+Content-Type: text/event-stream
+Cache-Control: no-cache
+Connection: keep-alive
+```
+
+### Debugging with Google Chrome
+
+Google Chrome provides build-in debugging and exploration tool for [Server-Sent
+Events](https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events)
+which is quite nice and available from Developer Tools under Network tab.
+
+> You can debug only client side events that get received and not the server
+> ones. For debugging server events add `console.log` to `server.js` code and
+> print out events.
+
+![Google Chrome Developer Tools EventStream](/assets/posts/simple-pubsub-server/chrome-debugging.png){:loading="lazy"}
+
+## Server implementation
+
+For the sake of this example we will use [Node.js](https://nodejs.org/en/) with
+[Express](https://expressjs.com) as our router since this is the easiest way to
+get started and we will use already written SSE library for node
+[sse-pubsub](https://www.npmjs.com/package/sse-pubsub) so we don't reinvent the
+wheel.
+
+```bash
+npm init --yes
+
+npm install express
+npm install body-parser
+npm install sse-pubsub
+```
+
+Basic implementation of a server (`server.js`):
+
+```js
+const express = require('express');
+const bodyParser = require('body-parser');
+const SSETopic = require('sse-pubsub');
+
+const app = express();
+const port = process.env.PORT || 4000;
+
+// topics container
+const sseTopics = {};
+
+app.use(bodyParser.json());
+
+// open for all cors
+app.all('*', (req, res, next) => {
+  res.header('Access-Control-Allow-Origin', '*');
+  res.header('Access-Control-Allow-Headers', 'X-Requested-With, Content-Type');
+  next();
+});
+
+// preflight request error fix
+app.options('*', async (req, res) => {
+  res.header('Access-Control-Allow-Origin', '*');
+  res.header('Access-Control-Allow-Headers', 'X-Requested-With, Content-Type');
+  res.send('OK');
+});
+
+// serve the event streams
+app.get('/stream/:topic', async (req, res, next) => {
+  const topic = req.params.topic;
+
+  if (!(topic in sseTopics)) {
+    sseTopics[topic] = new SSETopic({
+      pingInterval: 0,
+      maxStreamDuration: 15000,
+    });
+  }
+
+  // subscribing client to topic
+  sseTopics[topic].subscribe(req, res);
+});
+
+// accepts new messages into topic
+app.post('/publish', async (req, res) => {
+  let body = req.body;
+  let status = 200;
+
+  console.log('Incoming message:', req.body);
+
+  if (
+    body.hasOwnProperty('topic') &&
+    body.hasOwnProperty('event') &&
+    body.hasOwnProperty('message')
+  ) {
+    const topic = req.body.topic;
+    const event = req.body.event;
+    const message = req.body.message;
+
+    if (topic in sseTopics) {
+      // sends message to all the subscribers
+      sseTopics[topic].publish(message, event);
+    }
+  } else {
+    status = 400;
+  }
+
+  res.status(status).send({
+    status,
+  });
+});
+
+// returns JSON object of all opened topics
+app.get('/status', async (req, res) => {
+  res.send(sseTopics);
+});
+
+// health-check endpoint
+app.get('/', async (req, res) => {
+  res.send('OK');
+});
+
+// return a 404 if no routes match
+app.use((req, res, next) => {
+  res.set('Cache-Control', 'private, no-store');
+  res.status(404).end('Not found');
+});
+
+// starts the server
+app.listen(port, () => {
+  console.log(`PubSub server running on http://localhost:${port}`);
+});
+```
+
+### Our custom message format
+
+Each message posted on a server must be in a specific format that out server
+accepts. Having structure like this allows us to have multiple separated type of
+events on each topic.
+
+With this we can separate streams and only receive events that belong to the
+topic.
+
+One example would be, that we have index page and we want to receive messages
+about new upvotes or new subscribers but we don't want to follow events for
+other pages. This reduces clutter and overall network. And structure is much
+nicer and maintanable.
+
+```json
+{
+  "topic": "sample-topic",
+  "event": "sample-event",
+  "message": { "name": "John" }
+}
+```
+
+## Publisher and subscriber clients
+
+### Publisher and subscriber in action
+
+<video src="/assets/posts/simple-pubsub-server/clients.m4v" controls></video>
+
+You can download [the code](../simple-pubsub-server/sse-pubsub-server.zip) and
+follow along.
+
+### Publisher
+
+As talked about above publisher is the one that send messages to the
+broker/server. Message inside the payload can be whatever you want (string,
+object, array). I would however personally avoid send large chunks of data like
+blobs and such.
+
+```html
+<!DOCTYPE html>
+<html lang="en">
+
+  <head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Publisher</title>
+  </head>
+
+  <body>
+
+    <h1>Publisher</h1>
+
+    <fieldset>
+      <p>
+        <label>Server:</label>
+        <input type="text" id="server" value="http://localhost:4000">
+      </p>
+      <p>
+        <label>Topic:</label>
+        <input type="text" id="topic" value="sample-topic">
+      </p>
+      <p>
+        <label>Event:</label>
+        <input type="text" id="event" value="sample-event">
+      </p>
+      <p>
+        <label>Message:</label>
+        <input type="text" id="message" value='{"name": "John"}'>
+      </p>
+      <p>
+        <button type="button" id="button">Publish message to topic</button>
+      </p>
+    </fieldset>
+
+    <script>
+
+      const button = document.querySelector('#button');
+      const server = document.querySelector('#server');
+      const topic = document.querySelector('#topic');
+      const event = document.querySelector('#event');
+      const message = document.querySelector('#message');
+
+      button.addEventListener('click', async (evt) => {
+        const req = await fetch(`${server.value}/publish`, {
+          method: 'post',
+          headers: {
+            'Accept': 'application/json',
+            'Content-Type': 'application/json',
+          },
+          body: JSON.stringify({
+            topic: topic.value,
+            event: event.value,
+            message: JSON.parse(message.value),
+          }),
+        });
+
+        const res = await req.json();
+        console.log(res);
+      });
+
+    </script>
+
+  </body>
+
+</html>
+```
+
+### Subscriber
+
+Subscriber is responsible for receiving new messages that come from server via
+publisher. The code bellow is very rudimentary but works and follows the
+implementation guidelines for EventSource.
+
+You can use either Developer Tools Console to see incoming messages or you can
+defer to Debugging with Google Chrome section above to see all EventStream
+messages.
+
+> Don't be alarmed if the subscriber gets disconnected from the server every so
+> often. The code we have here resets connection every 15s but it automatically
+> get reconnected and fetches all messages up to last received message id. This
+> setting can be adjusted in `server.js` file; search for the
+> `maxStreamDuration` variable.
+
+```html
+<!DOCTYPE html>
+<html lang="en">
+
+  <head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Subscriber</title>
+    <link rel="stylesheet" href="style.css">
+  </head>
+
+  <body>
+
+    <h1>Subscriber</h1>
+
+    <fieldset>
+      <p>
+        <label>Server:</label>
+        <input type="text" id="server" value="http://localhost:4000">
+      </p>
+      <p>
+        <label>Topic:</label>
+        <input type="text" id="topic" value="sample-topic">
+      </p>
+      <p>
+        <label>Event:</label>
+        <input type="text" id="event" value="sample-event">
+      </p>
+      <p>
+        <button type="button" id="button">Subscribe to topic</button>
+      </p>
+    </fieldset>
+
+    <script>
+
+      const button = document.querySelector('#button');
+      const server = document.querySelector('#server');
+      const topic = document.querySelector('#topic');
+      const event = document.querySelector('#event');
+
+      button.addEventListener('click', async (evt) => {
+
+        let es = new EventSource(`${server.value}/stream/${topic.value}`);
+
+        es.addEventListener(event.value, function (evt) {
+          console.log(`incoming message`, JSON.parse(evt.data));
+        });
+
+        es.addEventListener('open', function (evt) {
+          console.log('connected', evt);
+        });
+
+        es.addEventListener('error', function (evt) {
+          console.log('error', evt);
+        });
+
+      });
+
+    </script>
+
+  </body>
+
+</html>
+```
+
+## Reading further
+
+- [Using server-sent events](https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events/Using_server-sent_events)
+- [Using SSE Instead Of WebSockets For Unidirectional Data Flow Over HTTP/2](https://www.smashingmagazine.com/2018/02/sse-websockets-data-flow-http2/)
+- [What is Server-Sent Events?](https://apifriends.com/api-streaming/server-sent-events/)
+- [An HTTP/2 extension for bidirectional messaging communication](https://tools.ietf.org/id/draft-xie-bidirectional-messaging-01.html)
+- [Introduction to HTTP/2](https://developers.google.com/web/fundamentals/performance/http2)
+- [The WebSocket API (WebSockets)](https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API)
+
diff --git a/_posts/posts/2020-03-27-create-placeholder-images-with-sharp.md b/_posts/posts/2020-03-27-create-placeholder-images-with-sharp.md
new file mode 100644
index 0000000..c129396
--- /dev/null
+++ b/_posts/posts/2020-03-27-create-placeholder-images-with-sharp.md
@@ -0,0 +1,103 @@
+---
+title: Create placeholder images with sharp Node.js image processing library
+permalink: /create-placeholder-images-with-sharp.html
+date: 2020-03-27T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+I have been searching for a solution to pre-generate some placeholder images for
+image server I needed to develop that resizes images on S3. I though this would
+be a 15min job and quickly found out how very mistaken I was.
+
+Even though Node.js is not really the best way to do this kind of things (surely
+something written in C or Rust or even Golang would be the correct way to do
+this but we didn't need the speed in our case) I found an excellent library
+[sharp - High performance Node.js image
+processing](https://github.com/lovell/sharp).
+
+Getting things running was a breeze.
+
+## Fetch image from S3 and save resized
+
+```js
+const sharp = require('sharp');
+const aws = require('aws-sdk');
+
+const x,y = 100;
+const s3 = new aws.S3({});
+
+aws.config.update({
+  secretAccessKey: 'secretAccessKey',
+  accessKeyId: 'accessKeyId',
+  region: 'region'
+});
+
+const originalImage = await s3.getObject({
+  Bucket: 'some-bucket-name',
+  Key: 'image.jpg',
+}).promise();
+
+const resizedImage = await sharp(originalImage.Body)
+  .resize(x, y)
+  .jpeg({ progressive: true })
+  .toBuffer();
+
+s3.putObject({
+  Bucket: 'some-bucket-name',
+  Key: `optimized/${x}x${y}/image.jpg`,
+  Body: resizedImage,
+  ContentType: 'image/jpeg',
+  ACL: 'public-read'
+}).promise();
+```
+
+All this code was wrapped inside a web service with some additional security 
+checks and defensive coding to detect if key is missing on S3.
+
+And at that point I needed to return placeholder images as a response in case
+key is missing or x,y are not allowed by the server etc. I could have created
+PNG in Gimp and just serve them but I wanted to respect aspect ratio and I
+didn't want to return some mangled images.
+
+> Main problem with finding a clean solution I could copy and paste and change a
+> bit was a task. API is changing constantly and there weren't clear examples or
+> I was unable to find them.
+
+## Generating placeholder images using SVG
+
+What I ended up was using SVG to generate text and created image with sharp and
+used composition to combine both layers. Response returned by this function is a
+buffer you can use to either upload to S3 or save to local file.
+
+```js
+const generatePlaceholderImageWithText = async (width, height, message) => {
+  const overlay = `<svg width="${width - 20}" height="${height - 20}">
+    <text x="50%" y="50%" font-family="sans-serif" font-size="16" text-anchor="middle">${message}</text>
+  </svg>`;
+
+  return await sharp({
+    create: {
+      width: width,
+      height: height,
+      channels: 4,
+      background: { r: 230, g: 230, b: 230, alpha: 1 }
+    }
+  })
+    .composite([{
+      input: Buffer.from(overlay),
+      gravity: 'center',
+    }])
+    .jpeg()
+    .toBuffer();
+}
+```
+
+That is about it. Nothing more to it. You can change the color of the image by
+changing `background` and if you want to change text styling you can adapt SVG
+to your needs.
+
+> Also be careful about the length of the text. This function positions text at
+> the center and adds `20px` padding on all sides. If text is longer than the
+> image it will get cut.
diff --git a/_posts/posts/2020-03-29-the-strange-case-of-elasticsearch-allocation-failure.md b/_posts/posts/2020-03-29-the-strange-case-of-elasticsearch-allocation-failure.md
new file mode 100644
index 0000000..1aa3536
--- /dev/null
+++ b/_posts/posts/2020-03-29-the-strange-case-of-elasticsearch-allocation-failure.md
@@ -0,0 +1,109 @@
+---
+title: The strange case of Elasticsearch allocation failure
+permalink: /the-strange-case-of-elasticsearch-allocation-failure.html
+date: 2020-03-29T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+I've been using Elasticsearch in production for 5 years now and never had a
+single problem with it. Hell, never even known there could be a problem. Just
+worked. All this time. The first node that I deployed is still being used in
+production, never updated, upgraded, touched in anyway.
+
+All this bliss came to an abrupt end this Friday when I got notification that
+Elasticsearch cluster went warm. Well, warm is not that bad right? Wrong!
+Quickly after that I got another email which sent chills down my spine.  Cluster
+is now red. RED! Now, shit really hit the fan!
+
+I tried googling what could be the problem and after executing allocation
+function noticed that some shards were unassigned and 5 attempts were already
+made (which is BTW to my luck the maximum) and that meant I am basically fucked.
+They also applied that one should wait for cluster to re-balance itself. So, I
+waited. One hour, two hours, several hours. Nothing, still RED.
+
+The strangest thing about it all was, that queries were still being fulfilled.
+Data was coming out. On the outside it looked like nothing was wrong but
+everybody that would look at the cluster would know immediately that something
+was very very wrong and we were living on borrowed time here.
+
+> **Please, DO NOT do what I did.** Seriously! Please ask someone on official
+forums or if you know an expert please consult him. There could be million of
+reasons and these solution fit my problem. Maybe in your case it would
+disastrous. I had all the data backed up and even if I would fail spectacularly
+I would be able to restore the data. It would be a huge pain and I would loose
+couple of days but I had a plan B.
+
+Executing allocation and told me what the problem was but no clear solution yet.
+
+```yaml
+GET /_cat/allocation?format=json
+```
+
+I got a message that `ALLOCATION_FAILED` with additional info `failed to create
+shard, failure ioexception[failed to obtain in-memory shard lock]`.  Well
+splendid! I must also say that our cluster is capable more than enough to handle
+the traffic. Also JVM memory pressure never was an issue. So what happened
+really then?
+
+I tried also re-routing failed ones with no success due to AWS restrictions on
+having managed Elasticsearch cluster (they lock some of the functions).
+
+```yaml
+POST /_cluster/reroute?retry_failed=true
+```
+
+I got a message that significantly reduced my options.
+
+```json
+{
+  "Message": "Your request: '/_cluster/reroute' is not allowed."
+}
+```
+
+After that I went on a hunt again. I won't bother you with all the details
+because hours/days went by until I was finally able to re-index the problematic
+index and hoped for the best. Until that moment even re-indexing was giving me
+errors.
+
+```yaml
+POST _reindex
+{
+  "source": {
+    "index": "myindex"
+  },
+  "dest": {
+    "index": "myindex-new"
+  }
+}
+```
+
+I needed to do this multiple times to get all the documents re-indexed. Then I
+dropped the original one with the following command.
+
+```yaml
+DELETE /myindex
+```
+
+And re-indexed again new one in the original one (well by name only).
+
+```yaml
+POST _reindex
+{
+  "source": {
+    "index": "myindex-new"
+  },
+  "dest": {
+    "index": "myindex"
+  }
+}
+```
+
+On the surface it looks like all is working but I have a long road in front of
+me to get all the things working again. Cluster now shows that it is in Green
+mode but I am also getting a notification that the cluster has processing status
+which could mean million of things.
+
+Godspeed!
+
diff --git a/_posts/posts/2020-03-30-my-love-and-hate-relationship-with-nodejs.md b/_posts/posts/2020-03-30-my-love-and-hate-relationship-with-nodejs.md
new file mode 100644
index 0000000..0299d9d
--- /dev/null
+++ b/_posts/posts/2020-03-30-my-love-and-hate-relationship-with-nodejs.md
@@ -0,0 +1,112 @@
+---
+title: My love and hate relationship with Node.js
+permalink: /my-love-and-hate-relationship-with-nodejs.html
+date: 2020-03-30T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+Previous project I was working on was being coded in
+[Golang](https://golang.org/). Also was my first project using it. And damn,
+that was an awesome experience. The whole thing is just superb. From how errors
+are handled. The C-like way you handle compiling. The way the language is
+structured making it incredibly versatile and easy to learn.
+
+It may cause some pain for somebody that is not used of using interfaces to map
+JSON and doing the recompilation all the time. But we have tools like
+[entr](http://eradman.com/entrproject/) and
+[make](https://www.gnu.org/software/make/) to fix that.
+
+But we are not here to talk about my undying love for **Golang**. Only in some
+way we probably should. It is an excellent example of how modern language should
+be designed. And because I have used it extensively in the last couple of years
+this probably taints my views of other languages. And is doing me a great
+disservice. Nevertheless, here we are.
+
+About two years ago I started flirting with [Node.js](https://nodejs.org/en/)
+for a project I started working on. What I wanted was to have things written in
+a language that is widely used, and we could get additional developers for.  As
+much as **Golang** is amazing it's really hard to get developers for it.  Even
+now. And after playing around with it for a week I felt in love with the speed
+of iteration and massive package ecosystem. Do you want SSO? You got it!  Do you
+want some esoteric library for something? There is a strong chance somebody
+wrote it. It is so extensive that you find yourself evaluating packages based on
+**GitHub stars** and number of contributors. You get swallowed by the vanity
+metrics and that potentially will become the downfall of Node.js.
+
+Because of the sheer amount of choice I often got anxiety when choosing
+libraries. Will I choose the correct one? Is this library something that will be
+supported for a foreseeable future or not? I am used of using libraries that are
+being in development for 10 years plus (Python, C) and that gave me some sort of
+comfort. And it is probably unfair to Node.js and community to expect same
+dedication.
+
+Moving forward ... Work started and things were great. **Speed of iteration was
+insane**. For some feature that I would need a day in Golang only took me hour
+or two. I became lazy! Using packages all over the place. Falling into the same
+trap as others. Packages on top of packages.  And [npm](https://www.npmjs.com/)
+didn't help at all. The way that the package manager works is just
+horrendous. And not allowing to have node_modules outside the project is also
+the stupidest idea ever.
+
+So at that point I started feeling the technical debt that comes with Node.js
+and the whole ecosystem. What nobody tells you is that **structuring large
+Node.js apps** is more problematic than one would think.  And going microservice
+for every single thing is also a bad idea. The amount of networking you
+introduce with that approach always ends up being a pain in the ass. And I don't
+even want to go into system administration here. The overhead is
+insane. Package-lock.json made many days feel like living hell for me. And I
+would eat the cost of all this if it meant for better development
+experience. Well, it didn't.
+
+The **lack of Typescript** support in the interpreter is still mind boggling to
+me. Why haven't they added native support yet for this is beyond me?! That would
+have solved so many problems. Lack of type safety became a problem somewhere in
+the middle of the project where the codebase was sufficiently large enough to
+present problems. We started adding arguments to functions and there was **no
+way to implicitly define argument types**. And because at that point there were
+a lot of functions, it became impossible to know what each one accepts,
+development became more and more trial and error based.
+
+I tried **implementing Typescript**, but that would present a large refactor
+that we were not willing to do at that point. The benefits were not enough.  I
+also tried [Flow - static type checker](https://flow.org/) but implementation
+was also horrible. What Typescript and Flow forces you is to have src folder and
+then **transpile** your code into dist folder and run it with node. WTH is that
+all about. Why can't this be done in memory or some virtual file system?  Why? I
+see no reason why this couldn't be done like this. But it is what it is.  I
+abandoned all hope for static type checking.
+
+One of the problems that resulted from not having interfaces or types was
+inability to model out our data from **Elasticsearch**. I could have done a
+**pedestrian implementation** of it, but there must be a better way of doing
+this without resorting to some hack basically. Or maybe I haven't found a
+solution, which is also a possibility. I have looked, though. No juice!
+
+**Error handling?** Is that a joke?
+
+Thank god for **await/async**. Without it, I would have probably just abandoned
+the whole thing and went with something else like Python. That's all I am going
+to say about this :)
+
+I started asking myself a question if Node.js is actually ready to be used in a
+**large scale applications**? And this was a totally wrong question. What I
+should have been asking myself was, how to use Node.js in large scale
+application. And you don't get this in **marketing material** for Express or Koa
+etc. They never tell you this. Making Node.js scale on infrastructure or in
+codebase is really **more of an art than a science**. And just like with the
+whole JavaScript ecosystem:
+
+- impossible to master,
+- half of your time you work on your tooling,
+- just accept transpilers that convert one code into another (holly smokes),
+- error handling is a joke,
+- standards? What standards?
+
+But on the other hand. As I did, you will also learn to love it. Learn to use it
+quickly and do impossible things in crazy limited time.
+
+I hate to admit it. But I love Node.js. Dammit, I love it :)
+
+**2023 Update**: I hate Node.js!
diff --git a/_posts/posts/2020-05-05-remote-work.md b/_posts/posts/2020-05-05-remote-work.md
new file mode 100644
index 0000000..8eb75d2
--- /dev/null
+++ b/_posts/posts/2020-05-05-remote-work.md
@@ -0,0 +1,73 @@
+---
+title: Remote work and how it affects the daily lives of people
+permalink: /remote-work.html
+date: 2020-05-05T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+I have been working remotely for the past 5 years. I love it. Love the freedom
+and make your schedule thingy.
+
+## You work more not less
+
+I've heard from people things like: "Oh, you are so lucky, working from home,
+having all the free time you want". It was obvious they had no clue what means
+working remotely. They had this romantic idea of remote work. You can watch TV
+whenever you like, you can go outside for a picnic if you want and stuff like
+that.
+
+This may be true if you work a day or two in a week from home. But if you go
+completely remote all these changes completely. I take some time to acclimate
+but then you start feeling the consequences of going fully remote. And it's not
+all rainbows and unicorns. Rather the opposite.
+
+## Feeling lost
+
+At first, I remembered I felt lost. I was not used to this kind of environment.
+It felt disoriented and a part of you that is used to procrastinate turns on.
+You start thinking of a workday as a whole day. And soon this idea of "I can do
+this later" starts creeping in. Well, I have the whole day ahead of me. I can do
+this a bit later.
+
+## Hyper-performance
+
+As a direct result, you become more focused on your work since you don't have
+all the interruptions common in the workplace. And you can quickly get used to
+this hyper-performance. But this mode requires also a lot of peace and quiet.
+
+And here we come to the ugly parts of all this. **People rarely have the
+self-control** to not waste other people's time. It is paralyzing when people
+start calling you, sending you chat messages, etc. The thing is, that when I
+achieve this hyper-performance mode I am completely embroiled in the problem I
+am solving and this kind of interruptions mess with your head. I need an hour at
+least to get back in the zone. Sometimes not achieving the same focus the whole
+day.
+
+I know that life is not how you want it to be and takes its route but from what
+I've learned this kind of interruptions can be avoided in 90% of the case easily
+just by closing any chat programs and putting your phone in a drawer.
+
+## Suggestion to all the new remote workers
+
+- Stop wasting other people's time. You don't bother people at their desks in
+  the office either.
+- Do not replace daily chats in the hallways with instant messaging software.
+  It will only interrupt people. Nothing good will come of it.
+- Set your working hours and try to not allow it to bleed outside these
+  boundaries and maintain your routine.
+- Be prepared that hours will be longer regardless of your good intentions and
+  your well thought of routine.
+- Try to be hyper-focused and do only one thing at the time. Multitasking is the
+  enemy of progress.
+- Avoid long meetings and if possible eliminate them. Rather take time to write
+  them out and allow others to respond in their own time. Meetings are usually a
+  large waste of time and most of the people attending them are there just
+  because the manager said so.
+- The software will not solve your problems. And throwing money at problems
+  neither.
+- If you are in a managerial position don't supervise any single minute of
+  workers. They are probably giving you more hours anyways. Track progress
+  weekly not daily. You hired them and give them the benefit of the doubt that
+  they will deliver what you agreed upon.
diff --git a/_posts/posts/2020-08-15-systemd-disable-wake-onmouse.md b/_posts/posts/2020-08-15-systemd-disable-wake-onmouse.md
new file mode 100644
index 0000000..8122322
--- /dev/null
+++ b/_posts/posts/2020-08-15-systemd-disable-wake-onmouse.md
@@ -0,0 +1,74 @@
+---
+title: Disable mouse wake from suspend with systemd service
+permalink: /disable-mouse-wake-from-suspend-with-systemd-service.html
+date: 2020-08-15T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+I recently bought [ThinkPad
+X220](https://www.laptopmag.com/reviews/laptops/lenovo-thinkpad-x220) just as a
+joke on eBay to test Linux distributions and play around with things and not
+destroy my main machine. Little to my knowledge I felt in love with it.  Man,
+they really made awesome machines back then.
+
+After changing disk that came with it to SSD and installing Ubuntu to test if 
+everything works I noticed that even after a single touch of my external mouse
+the system would wake up from sleep even though the lid was shut down.
+
+I wouldn't even noticed it if laptop didn't have [LED
+sleep indicator](https://support.lenovo.com/lk/en/solutions/~/media/Images/ContentImages/p/pd025386_x1_status_03.ashx?w=426&h=262).
+I already had a bad experience with Linux and it's power management. I had a
+[Dell Inspiron 7537](https://www.pcmag.com/reviews/dell-inspiron-15-7537) laptop
+with a touchscreen and while traveling it decided to wake up and started cooking
+in my backpack to the point that the digitizer responsible for touch actually
+glue off and the whole screen got wrecked. So, I am a bit touchy about this.
+
+I went on solution hunting and to my surprise there is no easy way to disable
+specific devices to perform wake up. Why is this not under the power management 
+tab in setting is really strange.
+
+After googling for a solution I found [this nice article describing the
+solution](https://codetrips.com/2020/03/18/ubuntu-disable-mouse-wake-from-suspend/)
+that worked for me. The only problem with this solution was that he added his
+solution to `.bashrc` and this triggers `sudo` that asks for a password each
+time new terminal is opened, which get annoying quickly since I open a lot of
+terminals all the time.
+
+I followed his instructions and got to solution `sudo sh -c "echo 'disabled' >
+/sys/bus/usb/devices/2-1.1/power/wakeup"`.
+
+I created a system service file `sudo nano
+/etc/systemd/system/disable-mouse-wakeup.service` and removed `sudo` and
+replaced `sh` with `/usr/bin/sh` and pasted all that in `ExecStart`.
+
+```ini
+[Unit]
+Description=Disables wakeup on mouse event
+After=network.target
+StartLimitIntervalSec=0
+
+[Service]
+Type=simple
+Restart=always
+RestartSec=1
+User=root
+ExecStart=/usr/bin/sh -c "echo 'disabled' > /sys/bus/usb/devices/2-1.1/power/wakeup"
+
+[Install]
+WantedBy=multi-user.target
+```
+
+After that I enabled, started and checked status of service.
+
+```sh
+sudo systemctl enable disable-mouse-wakeup.service
+sudo systemctl start disable-mouse-wakeup.service
+sudo systemctl status disable-mouse-wakeup.service
+```
+
+This will permanently disable that device from wakeing up you computer on boot.
+If you have many devices you would like to surpress from waking up your machine
+I would create a shell script and call that instead of direclty doing it in
+service file.
diff --git a/_posts/posts/2020-09-06-esp-and-micropython.md b/_posts/posts/2020-09-06-esp-and-micropython.md
new file mode 100644
index 0000000..bfd05d9
--- /dev/null
+++ b/_posts/posts/2020-09-06-esp-and-micropython.md
@@ -0,0 +1,226 @@
+---
+title: Getting started with MicroPython and ESP8266
+permalink: /esp8266-and-micropython-guide.html
+date: 2020-09-06T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Introduction
+
+A while ago I bought some
+[ESP8266](https://www.espressif.com/en/products/socs/esp8266) and
+[ESP32](https://www.espressif.com/en/products/socs/esp32) dev boards to play
+around with and I finally found a project to try it out.
+
+For my project, I used [ESP32](https://www.espressif.com/en/products/socs/esp32)
+but I could easily choose
+[ESP8266](https://www.espressif.com/en/products/socs/esp8266).  This guide
+contains which tools I use and how I prepared my workspace to code for
+[ESP8266](https://www.espressif.com/en/products/socs/esp8266).
+
+![ESP8266 and ESP32 boards](/assets/posts/esp8366-micropython/boards.jpg){:loading="lazy"}
+
+This guide covers:
+
+- flashing SOC
+- install proper tooling
+- deploying a simple script
+
+> Make sure that you are using **a good USB cable**. I had some problems with
+mine and once I replaced it everything started to work.
+
+## Flashing the SOC
+
+Plug your ESP8266 to USB port and check if the device was recognized with
+executing `dmesg | grep ch341-uart`.
+
+Then check if the device is available under `/dev/` by running `ls
+/dev/ttyUSB*`.
+
+> **Linux users**: if a device is not available be sure you are in `dialout`
+> group. You can check this by executing `groups $USER`. You can add a user to
+> `dialout` group with `sudo adduser $USER dialout`.
+
+After these conditions are meet go to the navigate to
+[https://micropython.org/download/esp8266/](https://micropython.org/download/esp8266/)
+and download `esp8266-20200902-v1.13.bin`.
+
+```sh
+mkdir esp8266-test
+cd esp8266-test
+
+wget https://micropython.org/resources/firmware/esp8266-20200902-v1.13.bin
+```
+
+After obtaining firmware we will need some tooling to flash the firmware to the
+board.
+
+```sh
+sudo pip3 install esptool
+```
+
+You can read more about `esptool` at
+[https://github.com/espressif/esptool/](https://github.com/espressif/esptool/).
+
+Before flashing the firmware we need to erase the flash on device. Substitute
+`USB0` with the device listed in output of `ls /dev/ttyUSB*`.
+
+```sh
+esptool.py --port /dev/ttyUSB0 erase_flash
+```
+
+If flash was successfully erased it is now time to flash the new firmware to it.
+
+```sh
+esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash --flash_size=detect 0 esp8266-20200902-v1.13.bin
+```
+
+If everything went ok you can try accessing MicroPython REPL with ` screen
+/dev/ttyUSB0 115200` or `picocom /dev/ttyUSB0 -b115200`.
+
+> Sometimes you will need to press `ENTER` in `screen` or `picocom` to access
+> REPL.
+
+When you are in REPL you can test if all is working properly following steps.
+
+```py
+> import machine
+> machine.freq()
+```
+
+This should output a number representing a frequency of the CPU (mine was
+`80000000`).
+
+When you are in `screen` or `picocom` these can help you a bit.
+
+| Key      | Command              |
+| -------- | -------------------- |
+| CTRL+d   | preforms soft reboot |
+| CTRL+a x | exits picocom        |
+| CTRL+a \ | exits screen         |
+
+
+## Install better tooling
+
+Now, to make our lives a little bit easier there are couple of additional tools
+that will make this whole experience a little more bearable.
+
+There are twq cool ways of uploading local files to SOC flash.
+
+- ampy → [https://github.com/scientifichackers/ampy](https://github.com/scientifichackers/ampy)
+- rshell → [https://github.com/dhylands/rshell](https://github.com/dhylands/rshell)
+
+### ampy
+
+```bash
+# installing ampy
+sudo pip3 install adafruit-ampy
+```
+
+Listed below are some common commands I used.
+
+```bash
+# uploads file to flash
+ampy --delay 2 --port /dev/ttyUSB0 put boot.py
+
+# lists file on flash
+ampy --delay 2 --port /dev/ttyUSB0 ls
+
+# outputs contents of file on flash
+ampy --delay 2 --port /dev/ttyUSB0 cat boot.py
+```
+
+> I added `delay` of 2 seconds because I had problems with executing commands.
+
+### rshell
+
+Even though `ampy` is a cool tool I opted with `rshell` in the end since it's
+much more polished and feature rich.
+
+```bash
+# installing ampy
+sudo pip3 install rshell
+```
+
+Now that `rshell` is installed we can connect to the board.
+
+```bash
+rshell --buffer-size=30 -p /dev/ttyUSB0 -a
+```
+
+This will open a shell inside bash and from here you can execute multiple
+commands. You can check what is supported with `help` once you are inside of a
+shell.
+
+```bash
+m@turing ~/Junk/esp8266-test
+$ rshell --buffer-size=30 -p /dev/ttyUSB0 -a
+
+Using buffer-size of 30
+Connecting to /dev/ttyUSB0 (buffer-size 30)...
+Trying to connect to REPL  connected
+Testing if ubinascii.unhexlify exists ... Y
+Retrieving root directories ... /boot.py/
+Setting time ... Sep 06, 2020 23:54:28
+Evaluating board_name ... pyboard
+Retrieving time epoch ... Jan 01, 2000
+Welcome to rshell. Use Control-D (or the exit command) to exit rshell.
+/home/m/Junk/esp8266-test> help
+
+Documented commands (type help <topic>):
+========================================
+args    cat  connect  date  edit  filesize  help  mkdir  rm     shell
+boards  cd   cp       echo  exit  filetype  ls    repl   rsync
+
+Use Control-D (or the exit command) to exit rshell.
+```
+
+> Inside a shell `ls` will display list of files on your machine. To get list
+> of files on flash folder `/pyboard` is remapped inside the shell. To list files
+> on flash you must perform `ls /pyboard`.
+
+#### Moving files to flash
+
+To avoid copying files all the time I used `rsync` function from the inside of
+`rshell`.
+
+```bash
+rsync . /pyboard
+```
+
+#### Executing scripts
+
+It is a pain to continuously reboot the device to trigger `/pyboard/boot.py` and
+there is a better way of testing local scripts on remote device.
+
+Lets assume we have `src/freq.py` file that displays CPU frequency of a remote
+device.
+
+```py
+# src/freq.py
+
+import machine
+print(machine.freq())
+```
+
+Now lets upload this and execute it.
+
+```bash
+# syncs files to remove device
+rsync ./src /pyboard
+
+# goes into REPL
+repl
+
+# we import file by importing it without .py extension and this will run the script
+> import freq
+
+# CTRL+x will exit REPL
+```
+
+## Additional resources
+
+- https://randomnerdtutorials.com/getting-started-micropython-esp32-esp8266/
+- http://docs.micropython.org/en/latest/esp8266/quickref.html
diff --git a/_posts/posts/2020-09-08-bind-warning-on-login.md b/_posts/posts/2020-09-08-bind-warning-on-login.md
new file mode 100644
index 0000000..4b2c983
--- /dev/null
+++ b/_posts/posts/2020-09-08-bind-warning-on-login.md
@@ -0,0 +1,55 @@
+---
+title: Fix bind warning in .profile on login in Ubuntu
+permalink: /bind-warning-on-login-in-ubuntu.html
+date: 2020-09-08T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+Recently I moved back to [bash](https://www.gnu.org/software/bash/) as my
+default shell. I was previously using [fish](https://fishshell.com/) and got
+used to the cool features it has. But, regardless of that, I wanted to move to a
+more standard shell because I was hopping back and forth with exporting
+variables and stuff like that which got pretty annoying.
+
+So I embarked on a mission to make [bash](https://www.gnu.org/software/bash/)
+more like [fish](https://fishshell.com/) and in the process found that I really
+missed autosuggest with TAB on changing directories.
+
+I found a nice alternative that emulates [zsh](http://zsh.sourceforge.net/) like
+autosuggestion and autocomplete so I added the following to my `.bashrc` file.
+
+```bash
+bind "TAB:menu-complete"
+bind "set show-all-if-ambiguous on"
+bind "set completion-ignore-case on"
+bind "set menu-complete-display-prefix on"
+bind '"\e[Z":menu-complete-backward'
+```
+
+I haven't noticed anything wrong with this and all was working fine until I
+restarted my machine and then I got this error.
+
+![Profile bind error](/assets/posts/profile-bind-error/error.jpg){:loading="lazy"}
+
+When I pressed OK, I got into the [Gnome
+shell](https://wiki.gnome.org/Projects/GnomeShell) and all was working fine, but
+the error was still bugging me. I started looking for the reason why this is
+happening and found a solution to this error on [Remote SSH Commands - bash bind
+warning: line editing not enabled](https://superuser.com/a/892682).
+
+So I added a simple `if [ -t 1 ]` around `bind` statements to avoid running
+commands that presume the session is interactive when it isn't.
+
+```bash
+if [ -t 1 ]; then
+  bind "TAB:menu-complete"
+  bind "set show-all-if-ambiguous on"
+  bind "set completion-ignore-case on"
+  bind "set menu-complete-display-prefix on"
+  bind '"\e[Z":menu-complete-backward'
+fi
+```
+
+After logging out and back in the problem was gone.
diff --git a/_posts/posts/2020-09-09-digitalocean-sync.md b/_posts/posts/2020-09-09-digitalocean-sync.md
new file mode 100644
index 0000000..38696a9
--- /dev/null
+++ b/_posts/posts/2020-09-09-digitalocean-sync.md
@@ -0,0 +1,113 @@
+---
+title: Using Digitalocean Spaces to sync between computers
+permalink: /digitalocean-spaces-to-sync-between-computers.html
+date: 2020-09-09T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+I've been using [Dropbox](https://www.dropbox.com/) for probably **10+ years**
+now and I-ve became so used to it that it runs in the background that I don't
+even imagine a world without it. But it's not without problems.
+
+At first I had problems with `.venv` environments for Python and the only
+solution for excluding synchronization for this folder was to manually exclude a
+specific folder which is not really scalable. FYI, my whole project folder is
+synced on [Dropbox](https://www.dropbox.com/). This of course introduced a lot
+of syncing of files and folders that are not needed or even break things on
+other machines. In the case of **Python**, I couldn't use that on my second
+machine. I needed to delete `.venv` folder and pip it again which synced files
+again to the main machine. This was very frustrating. **Nodejs** handles this
+much nicer and I can just run the scripts without deleting `node_modules` again
+and reinstalling. However, `node_modules` is a beast of its own. It creates so
+many files that OS has a problem counting them when you check the folder
+contents for size.
+
+I wanted something similar to Dropbox. I could without the instant syncing but
+it would need to be fast and had the option for me to exclude folders like
+`node_modules, .venv, .git` and folders like that.
+
+I went on a hunt for an alternative to [Dropbox](https://www.dropbox.com/) 
+and found:
+
+- [Tresorit](https://tresorit.com/)
+- [Sync.com](https://sync.com)
+- [Box](https://www.box.com/)
+
+You know, the usual list of suspects. I didn't include [Google
+drive](https://drive.google.com) or [One drive](https://onedrive.live.com/)
+since they are even more draconian than Dropbox.
+
+> All this does not stem from me being paranoid but recently these companies 
+> have became more and more aggressive and they keep violating our privacy when 
+> they share our data with 3rd party services. It is getting out of control.
+
+So, my main problem was still there. No way of excluding a specific folder from
+syncing. And before we go into "*But you have git, isn't that enough?*", I must
+say, that many of the files (PDFs, spreadsheets, etc) I have in a `git` repo
+don't get pushed upstream to Git and I still want to have them synced across my
+computers.
+
+I initially wanted to use [rsync](https://linux.die.net/man/1/rsync) but I would
+need to then have a remote VPS or transfer between my computers directly.  I
+wanted a solution where all my files could be accessible to me without my
+machine.
+
+> **WARNING: This solution will cost you money!** DigitalOcean Spaces are $5 per
+month and there are some bandwidth limitations and if you go beyond that you get
+billed additionally.
+
+Then I remembered that I could use something like
+[S3](https://en.wikipedia.org/wiki/Amazon_S3) since it has versioning and is
+fully managed. I didn't want to go down the AWS rabbit hole with this so I
+choose [DigitalOcean Spaces](https://www.digitalocean.com/products/spaces/).
+
+Then I needed a command-line tool to sync between source and target. I found
+this nice tool [s3cmd](https://s3tools.org/s3cmd) and it is in the Ubuntu
+repositories.
+
+```bash
+sudo apt install s3cmd
+```
+
+After installation will I create a new Space bucket on DigitalOcean. Remember
+the zone you will choose because you will need it when you will configure
+`s3cmd`.
+
+Then I visited [Digitalocean Applications &
+API](https://cloud.digitalocean.com/account/api/tokens) and generated **Spaces
+access keys**. Save both key and secret somewhere safe because when you will
+leave the page secret will not be available anymore to you and you will need to
+re-generate it.
+
+```bash
+# enter your key and secret and correct endpoint
+# my endpoint is ams3.digitaloceanspaces.com because
+# I created my bucket in Amsterdam regiin
+s3cmd --configure
+```
+
+After that I played around with options for `s3cmd` and got to the following
+command.
+
+```bash
+# I executed this command from my projects folder
+cd projects
+s3cmd sync --delete-removed --exclude 'node_modules/*' --exclude '.git/*' --exclude '.venv/*' ./ s3://my-bucket-name/projects/
+```
+
+When syncing int he other direction you will need to change the order of the 
+`SOURCE` and `TARGET` to `s3://my-bucket-name/projects/` and `./`.
+
+> Be sure that all the paths have trailing slash so that sync knows that this 
+> are directories.
+
+I am planning to implement some sort of a `.ignore` file that will enable me to
+have a project-specific exclude options.
+
+I am currently running this every hour as a cronjob which is perfectly fine for
+now when I am testing how this whole thing works and how it all will turn out.
+
+I have also created a small Gnome extension which is still very unstable, but
+when/if this whole experiment pays of I will share on Github.
diff --git a/_posts/posts/2021-01-24-replacing-dropbox-with-s3.md b/_posts/posts/2021-01-24-replacing-dropbox-with-s3.md
new file mode 100644
index 0000000..7599949
--- /dev/null
+++ b/_posts/posts/2021-01-24-replacing-dropbox-with-s3.md
@@ -0,0 +1,115 @@
+---
+title: Replacing Dropbox in favor of DigitalOcean spaces
+permalink: /replacing-dropbox-in-favor-of-digitalocean-spaces.html
+date: 2021-01-24T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+A few months ago I experimented with DigitalOcean spaces as my backup solution
+that could [replace Dropbox
+eventually](/digitalocean-spaces-to-sync-between-computers.html).  That solution
+worked quite nicely, and I was amazed how smashing together a couple of existing
+solutions would work this fine.
+
+I have been running that solution in the background for a couple of months now
+and kind of forgot about it. But recent developments around deplatforming and
+having us people hostages of technology and big companies speed up my goals to
+become less dependent on
+[Google](https://edition.cnn.com/2020/12/17/tech/google-antitrust-lawsuit/index.html),
+[Dropbox](https://www.pcworld.com/article/2048680/dropbox-takes-a-peek-at-files.html)
+etc and take back some control.
+
+I am not a conspiracy theory nut, but to be honest, what these companies are
+doing lately is out of control. It is a matter of principle at this point. I
+have almost completely degoogled my life all the way from ditching Gmail,
+YouTube and most of the services surrounding Google. And I must tell you, I feel
+so good. I haven't felt this way for a long time.
+
+**Anyways. Let's get to the meat of things.**
+
+Before you continue you should read my post about [syncing to
+Dropbox](/digitalocean-spaces-to-sync-between-computers.html).
+
+> Also to note, I am using Linux on my machine with Gnome desktop environment.
+This should work on MacOS too. To use this on Windows I suggest using
+[Subsystem for Linux](https://docs.microsoft.com/en-us/windows/wsl/install-win10)
+or [Cygwin](https://www.cygwin.com/).
+
+## Folder structure
+
+I liked structure from Dropbox. One folder where everything is located and
+synced. So, that's why adopted this also for my sync setup.
+
+```go
+~/Vault
+   ↳ backup
+   ↳ bin
+   ↳ documents
+   ↳ projects
+```
+
+All of my code is located in `~/Vault/projects` folder. And most of the projects
+are Git repositories. I do not use this sync method for backup per see but in
+case I reinstall my machine I can easily recreate all the important folder
+structure with one quick command. No external drives needed that can fail etc.
+
+## Sync script
+
+My sync script is located in `~/Vault/bin/vault-backup.sh`
+
+```bash
+#!/bin/bash
+
+# dconf load /com/gexperts/Tilix/ < tilix.dconf
+# 0 2 * * * sh ~/Vault/bin/vault-backup.sh
+
+cd ~/Vault/backup/dotfiles
+
+MACHINE=$(whoami)@$(hostname)
+mkdir -p $MACHINE
+cd $MACHINE
+
+cp ~/.config/VSCodium/User/settings.json settings.json
+cp ~/.s3cfg s3cfg
+cp ~/.bash_extended bash_extended
+cp ~/.ssh ssh -rf
+
+codium --list-extensions > vscode-extension.txt
+dconf dump /com/gexperts/Tilix/ > tilix.dconf
+
+cd ~/Vault
+s3cmd sync --delete-removed --exclude 'node_modules/*' --exclude '.git/*' --exclude '.venv/*' ./ s3://bucket-name/backup/
+
+echo `date +"%D %T"` >> ~/.vault.log
+
+notify-send \
+        -u normal \
+        -i /usr/share/icons/Adwaita/96x96/status/security-medium-symbolic.symbolic.png \
+        "Vault sync succeded at `date +"%D %T"`"
+```
+
+This script also backups some of the dotfiles I use and sends notification to
+Gnome notification center. It is a straightforward solution. Nothing special
+going on.
+
+> One obvious benefit of this is that I can omit syncing Node's `node_modules`
+> or Python's `.venv` and `.git` folders.
+
+You can use this script in a combination with [Cron](https://en.wikipedia.org/wiki/Cron).
+
+```txt
+0 2 * * * sh ~/Vault/bin/vault-backup.sh
+```
+
+When you start syncing your local stuff with a remote server you can review your
+items on DigitalOcean.
+
+![Dropbox Spaces](/assets/posts/dropbox-sync/dropbox-spaces.png){:loading="lazy"}
+
+I have been using this script now for quite some time, and it's working
+flawlessly. I also uninstalled Dropbox and stopped using it completely.
+
+All I need to do is write a Bash script that does the reverse and downloads from
+remote server to local folder. This could be another post.
diff --git a/_posts/posts/2021-01-25-goaccess.md b/_posts/posts/2021-01-25-goaccess.md
new file mode 100644
index 0000000..779bce5
--- /dev/null
+++ b/_posts/posts/2021-01-25-goaccess.md
@@ -0,0 +1,205 @@
+---
+title: Using GoAccess with Nginx to replace Google Analytics
+permalink: /using-goaccess-with-nginx-to-replace-google-analytics.html
+date: 2021-01-25T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Introduction
+
+I know! You cannot simply replace Google Analytics with parsing access logs and
+displaying a couple of charts. But to be honest, I actually never used Google
+Analytics to the fullest extent and was usually interested in seeing page hits
+and which pages were visited most often.
+
+I recently moved my blog from Firebase to a VPS and also decided to remove
+Google Analytics tracking code from the site since its quite malicious and
+tracks users across other pages also and is creating a profile of a user, and
+I've had it. But I also need some insight of what is happening on a server and
+which content is being read the most etc.
+
+I have looked at many existing solutions like:
+
+- [Umami](https://umami.is/)
+- [Freshlytics](https://github.com/sheshbabu/freshlytics)
+- [Matomo](https://matomo.org/)
+
+But the more I looked at them the more I noticed that I am replacing one evil
+with another one. Don't get me wrong. Some of these solutions are absolutely
+fantastic but would require installation of databases and something like PHP or
+Node. And I was not ready to put those things on my fresh server. Also having
+Docker installed is out of the question.
+
+## Opting for log parsing
+
+So, I defaulted to parsing already existing logs and generating HTML reports
+from this data.
+
+I found this amazing software [GoAccess](https://goaccess.io/) which provides
+all the functionalities I need, and it's a single binary. Written in Go.
+
+GoAccess can be used in two different modes.
+
+![GoAccess Terminal](/assets/posts/goaccess/goaccess-dash-term.png){:loading="lazy"}
+
+*Running in a terminal*
+
+![GoAccess HTML](/assets/posts/goaccess/goaccess-dash-html.png){:loading="lazy"}
+
+*Running in a browser*
+
+I, however, need this to run in a browser. So, the second option is the way to
+go. The Idea is to periodically run cronjob and export this report into a folder
+that gets then server by Nginx behind a Basic authentication.
+
+## Getting Nginx ready
+
+I choose Ubuntu on [DigitalOcean](https://www.digitalocean.com/). First I
+installed [Nginx](https://nginx.org/en/), and
+[Letsencrypt](https://letsencrypt.org/getting-started/) certbot and all the
+necessary dependencies.
+
+```sh
+# log in as root user
+sudo su -
+
+# first let's update the system
+apt update && apt upgrade -y
+
+# let's install
+apt install nginx certbot python3-certbot-nginx apache2-utils
+```
+
+After all this is installed we can create a new configuration for a statistics.
+Stats will be available at `stats.domain.com`.
+
+```sh
+# creates directory where html will be hosted
+mkdir -p /var/www/html/stats.domain.com
+
+cp /etc/nginx/sites-available/default /etc/nginx/sites-available/stats.domain.com
+nano /etc/nginx/sites-available/stats.domain.com
+```
+
+```nginx
+server {
+  root /var/www/html/stats.domain.com;
+  server_name stats.domain.com;
+
+  index index.html;
+  location / {
+    try_files $uri $uri/ =404;
+  }
+}
+```
+
+Now we check if the configuration is ok. We can do this with `nginx -t`. If all
+is ok, we can restart Nginx with `service nginx restart`.
+
+After all that you should add A record for this domain that points to IP of a
+droplet.
+
+Before enabling SSL you should test if DNS records have propagated with `curl
+stats.domain.com`.
+
+Now, it's time to provision TLS certificate. To achieve this, you execute
+command `certbot --nginx`. Follow the wizard and when you are asked about
+redirection always choose 2 (always redirect to HTTPS).
+
+When this is done you can visit https://stats.domain.com and you should get 404
+not found error which is correct.
+
+## Getting GoAccess ready
+
+If you are using Debian like system GoAccess should be available in repository.
+Otherwise refer to the official website.
+
+```sh
+apt install goaccess
+```
+
+To enable Geo location we also need one additiona thing.
+
+```sh
+cd /var/www/html/stats.stats.com
+wget https://github.com/P3TERX/GeoLite.mmdb/raw/download/GeoLite2-City.mmdb
+```
+
+Now we create a shell script that will be executed every 10 minutes.
+
+```sh
+nano /var/www/html/stats.domain.com/generate-stats.sh
+```
+
+Contents of this file should look like this.
+
+```sh
+#!/bin/sh
+
+zcat -f /var/log/nginx/access.log* > /var/log/nginx/access-all.log
+
+goaccess \
+  --log-file=/var/log/nginx/access-all.log \
+  --log-format=COMBINED \
+  --exclude-ip=0.0.0.0 \
+  --geoip-database=/var/www/html/stats.domain.com/GeoLite2-City.mmdb \
+  --ignore-crawlers \
+  --real-os \
+  --output=/var/www/html/stats.domain.com/index.html
+
+rm /var/log/nginx/access-all.log
+```
+
+Because after a while nginx creates multiple files with access logs we use
+[`zcat`](https://linux.die.net/man/1/zcat) to extract Gziped contents and create
+a file that has all the access logs. After this file is used we delete it.
+
+If you want to exclude your home IP's result look at the `--exclude-ip` option
+in script and instead of `0.0.0.0` add your own home IP address. You can find
+your home IP by executing `curl ifconfig.me` from your local machine and NOT
+from the droplet.
+
+Test the script by executing `sh
+/var/www/html/stats.domain.com/generate-stats.sh` and then checking
+`https://stats.domain.com`. If you can see stats instead of 404 than you are
+set.
+
+It's time to add this script to cron with `cron -e`.
+
+```go
+*/10 * * * * sh /var/www/html/stats.domain.com/generate-stats.sh
+```
+
+## Securing with Basic authentication
+
+You probably don't want stats to be publicly available, so we should create a
+user and a password for Basic authentication.
+
+First we create a password for a user `stats` with `htpasswd -c /etc/nginx/.htpasswd stats`.
+
+Now we update config file with `nano
+/etc/nginx/sites-available/stats.domain.com`.  You probably noticed that the
+file looks a bit different from before. This is because `certbot` added
+additional rules for SSL.
+
+Your location portion the config file should now look like. You should add
+`auth_basic` and `auth_basic_user_file` lines to the file.
+
+```nginx
+location / {
+  try_files $uri $uri/ =404;
+  auth_basic "Private Property";
+  auth_basic_user_file /etc/nginx/.htpasswd;
+}
+```
+
+Test if config is still ok with `nginx -t` and if it is you can restart Nginx
+with `service nginx restart`.
+
+If you now visit `https://stats.domain.com` you should be prompted for username
+and password. If not, try reopening your browser.
+
+That is all. You now have analytics for your server that gets refreshed every 10
+minutes.
diff --git a/_posts/posts/2021-06-26-simple-world-clock.md b/_posts/posts/2021-06-26-simple-world-clock.md
new file mode 100644
index 0000000..d1b53b4
--- /dev/null
+++ b/_posts/posts/2021-06-26-simple-world-clock.md
@@ -0,0 +1,108 @@
+---
+title: Simple world clock with eInk display and Raspberry Pi Zero
+permalink: /simple-world-clock-with-eiink-display-and-raspberry-pi-zero.html
+date: 2021-06-26T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+Our team is spread across the world, from the USA all the way to Australia, so
+having some sort of world clock makes sense.
+
+Currently, I am using an extension for Gnome called [Timezone
+extension](https://extensions.gnome.org/extension/2657/timezones-extension/),
+and it serves the purpose quite well.
+
+But I also have a bunch of electronics that I bought through the time, and I am
+not using any of them, and it's time to stop hording this stuff and use it in a
+project.
+
+A while ago I bought a small eInk display [Inky
+pHAT](https://shop.pimoroni.com/products/inky-phat?variant=12549254217811) and I
+have a bunch of [Raspberry Pi's
+Zero](https://www.raspberrypi.org/products/raspberry-pi-zero/) lying around that
+I really need to use.
+
+![Inky pHAT, Raspberry Pi Zero](/assets/posts/world-clock/hardware.jpg){:loading="lazy"}
+
+Since the Inky [Inky
+pHAT](https://shop.pimoroni.com/products/inky-phat?variant=12549254217811) is
+essentially a HAT, it can easily be added on top of the [Raspberry Pi
+Zero](https://www.raspberrypi.org/products/raspberry-pi-zero/).
+
+First, I installed the necessary software on Raspberry Pi with `pip3 install
+inky`.
+
+And then I created a file `clock.py` in home directory `/home/pi`.
+
+```python
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import sys
+import os
+from inky.auto import auto
+from PIL import Image, ImageFont, ImageDraw
+from font_fredoka_one import FredokaOne
+
+clocks = [
+  'America/New_York',
+  'Europe/Ljubljana',
+  'Australia/Brisbane',
+]
+
+board = auto()
+board.set_border(board.WHITE)
+board.rotation = 90
+
+img = Image.new('P', (board.WIDTH, board.HEIGHT))
+draw = ImageDraw.Draw(img)
+
+big_font = ImageFont.truetype(FredokaOne, 18)
+small_font = ImageFont.truetype(FredokaOne, 13)
+
+x = board.WIDTH / 3
+y = board.HEIGHT / 3
+
+idx = 1
+for clock in clocks:
+  ctime = os.popen('TZ="{}" date +"%a,%H:%M"'.format(clock))
+  ctime = ctime.read().strip().split(',')
+  city = clock.split('/')[1].replace('_', ' ')
+
+  draw.text((15, (idx*y)-y+10), city, fill=board.BLACK, font=small_font)
+  draw.text((110, (idx*y)-y+7), str(ctime[0]), fill=board.BLACK, font=big_font)
+  draw.text((155, (idx*y)-y+7), str(ctime[1]), fill=board.BLACK, font=big_font)
+
+  idx += 1
+
+board.set_image(img)
+board.show()
+```
+
+And because eInk displays are rather slow to refresh and the clock requires
+refreshing only once a minute, this can be done through cronjob.
+
+Before we add this job to cron we need to make `clock.py` executable with `chmod
++x clock.py`.
+
+Then we add a cronjob with `crontab -e`.
+
+```txt
+* * * * * /home/pi/clock.py
+```
+
+So, we end up with a result like this.
+
+![World Clock](/assets/posts/world-clock/world-clock.jpg){:loading="lazy"}
+
+And for the enclosure that can be 3D printed, but I haven't yet something like
+this can be used.
+
+<iframe id="vs_iframe" src="https://www.viewstl.com/?embedded&url=https%3A%2F%2Fmitjafelicijan.com%2Fposts%2Fworld-clock%2Fenclosure.stl&color=gray&bgcolor=white&edges=no&orientation=front&noborder=no" style="border:0;margin:0;width:100%;height:400px;"></iframe>
+
+You can download my [STL file for the enclosure
+here](/assets/posts/world-clock/enclosure.stl), but make sure that dimensions make
+sense and also opening for USB port should be added or just use a drill and some
+hot glue to make it stick in the enclosure.
diff --git a/_posts/posts/2021-07-30-from-internet-consumer-to-full-hominum-again.md b/_posts/posts/2021-07-30-from-internet-consumer-to-full-hominum-again.md
new file mode 100644
index 0000000..cbcca37
--- /dev/null
+++ b/_posts/posts/2021-07-30-from-internet-consumer-to-full-hominum-again.md
@@ -0,0 +1,104 @@
+---
+title: My journey from being an internet über consumer to being a full hominum again
+permalink: /from-internet-consumer-to-full-hominum-again.html
+date: 2021-07-30T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+It's been almost a year since I started purging all my online accounts and 
+going down this rabbit hole of being almost independent of the current internet
+machine. Even though I initially thought that I will have problems adapting,
+I was pleasantly surprised that the transition went so smoothly. Even better,
+it brought many benefits to my life. Such as increased focus, less stress
+about trivial things, etc.
+
+It all started with me doing small changes like unsubscribing from emails that I
+have either subscribed to by accepting terms and conditions. Or even some more
+malicious emails that I was getting because I was on a shared mailing list. And
+the later ones I hate the most of all. How the hell do they keep sharing my
+email and sending me unsolicited emails and get away with it? I have a suspicion
+that these marketing people share an Excel file between them and keep
+resubscribing me when they import lists into Mailchimp or similar software.
+
+It's fascinating to see how much crap you get subscribed to when you are not
+paying attention. It got so bad that my primary Gmail address is a full of junk
+and need constant monitoring and cleaning up. And because I want to have Inbox
+Zero, this presents an additional problem for me.
+
+The stress that email presented for me didn't occur to me for a long time. I was
+noticing that I was unable to go through one single hour without hysterically
+refreshing email. And if somebody wrote me something, I needed to see it right
+then, even though I didn't immediately reply to it. I can only describe this
+with FOMO (fear of missing out). I have no other explanation than that. It was
+crippling, and I was constantly context switching, which I will address further
+down this post in more details.
+
+This was one of the reasons why I spawned up my personal email server, and I am
+using it now as my primary and person email. I still have Gmail as my “junk”
+email that I use for throw away stuff. I log in to Gmail once a week and check
+if there are any important emails that I got, but apart from that, it's sitting
+dormant and collecting dust.
+
+The more I was watching the world loose it's self with allowing anti freedom
+things to happen to it, the more I started to realize that something has to
+change. I don't have the power to change the world. And I also don't have a
+grandiose opinion of myself to even think to try it. But what I can do is to not
+subscribe to this consumer way of thinking. I will not be complicit in this. My
+moral and ethical stances won't allow it. So, this brings us to the second part
+of my journey.
+
+I was using all these 3rd party services because I was either lazy or OK with
+the drawbacks of them. I watched these services and companies became more and
+privacy policies and everybody is OK with accepting them, and they pray on that
+more evil. It is evil if you sell your user's data in this manner. Nobody reads
+flaw in human nature. I really hate the hypocrisy they manage to muster. These
+companies prey on our laziness, and we are at fault here. Nobody else. And I
+truly understand the reasons why we rather accept and move on, and not object
+and have our lives a little more difficult. They have perfected this through
+years of small changes that make us a little more dependent on them. You could
+not convince a person to give away all his rights and data in one day. This was
+gradual and slow. And it caught us all in surprise. When I really stopped and
+thought about it, I felt repulsed. By really stopping and thinking about it, I
+really mean stopping and thinking about it. Thoroughly and in depth.
+
+Each step I took depleted my character a bit more. Like I was trading myself bit
+by bit without understanding what it all meant. What it meant to be a full
+person, not divided by all this bought attention they want from me. They don't
+just get your data, but they also take your attention away from you. They
+scatter your and go with the divide and conquer tactic from there. And a person
+divided is a person not fully there. Not at the moment. Not alive fully.
+
+I was unable to form long thoughts. Well, I thought I was. But now that I see
+what being a full person is again, I can see that I was not at my 100% back
+then.
+
+A revolt was inevitable. There was no other way of continuing my story without
+it. Without taking back my attention, my thoughts, my time, and my privacy,
+regardless of how too late it maybe is.
+
+This has nothing to do with conspiracy theories. Even less with changing the
+world. All I wanted was to get my life back in order and not waste the energy
+that could be spent in other, better places.
+
+I started reading more. I can focus now fully on things I work on. Furthermore,
+I have the mental acuity that I never had before. My mind feels sharp. I don't
+get angry so much. I can cherish the finer things in life now without the need
+to interpret them intellectually. Not only that, but I have a feeling of
+belonging again. Sense of purpose has returned with a vengeance. And I can now
+help people without depleting myself.
+
+The last step so far was to finish closing all the remaining online accounts
+that I still had. And when I was thinking what value they bring me, I wasn't
+surprised that the answer was none. I wasn't logging in them and using them.  I
+stopped being afraid of FOMO. If somebody wants to get in contact me, they will
+find a way. I am one search away.
+
+We are not beholden to anybody. Our lives are our own. So dare yourself to
+delete Facebook, LinkedIn. To unsubscribe. Dare yourself to take your time and
+attention back. Use that time and energy to go for a walk without thinking about
+work. Read a book instead of reading comment on social media that you will
+forget in an hour. Enrich your life instead of wasting it. It only requires a
+small step. And you will feel the benefits immediately. Lose the weight of the
+world that is crushing you without your consent.
diff --git a/_posts/posts/2021-08-01-linux-cheatsheet.md b/_posts/posts/2021-08-01-linux-cheatsheet.md
new file mode 100644
index 0000000..b416ffa
--- /dev/null
+++ b/_posts/posts/2021-08-01-linux-cheatsheet.md
@@ -0,0 +1,288 @@
+---
+title: List of essential Linux commands for server management
+permalink: /linux-cheatsheet.html
+date: 2021-08-01T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+**Generate SSH key**
+
+```bash
+ssh-keygen -t ed25519 -C "your_email@example.com"
+
+# when no support for Ed25519 present
+ssh-keygen -t rsa -b 4096 -C "your_email@example.com"
+```
+
+Note: By default SSH keys get stored to `/home/<username>/.ssh/` folder.
+
+**Login to host via SSH**
+
+```bash
+# connect to host as your local username
+ssh host
+
+# connect to host as user
+ssh <user>@<host>
+
+# connect to host using port
+ssh -p <port> <user>@<host>
+```
+
+**Execute command on a server through SSH**
+
+```bash
+# execute one command
+ssh root@100.100.100.100 "ls /root"
+
+# execute many commands
+ssh root@100.100.100.100 "cd /root;touch file.txt"
+```
+
+**Displays currently logged in users in the system**
+
+```bash
+w
+```
+
+**Displays Linux system information**
+
+```bash
+uname
+```
+
+**Displays kernel release information**
+
+```bash
+uname -r
+```
+
+**Shows the system hostname**
+
+```bash
+hostname
+```
+
+**Shows system reboot history**
+
+```bash
+last reboot
+```
+
+**Displays information about the user**
+
+```bash
+sudo apt install finger
+finger <username>
+```
+
+**Displays IP addresses and all the network interfaces**
+
+```bash
+ip addr show
+```
+
+**Downloads a file from an online source**
+
+```bash
+wget https://example.com/example.tgz
+```
+
+Note: If URL contains ?, & enclose the URL in double quotes.
+
+**Compress a file with gzip**
+
+```bash
+# will not keep the original file
+gzip file.txt
+
+# will keep the original file
+gzip --keep file.txt
+```
+
+**Interactive disk usage analyzer**
+
+```bash
+sudo apt install ncdu
+
+ncdu
+ncdu <path/to/directory>
+```
+
+**Install Node.js using the Node Version Manager**
+
+```bash
+curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.3/install.sh | bash
+source ~/.bashrc
+
+nvm install v13
+```
+
+**Too long; didn't read**
+
+```bash
+npm install -g tldr
+
+tldr tar
+```
+
+**Combine all Nginx access logs to one big log file**
+
+```bash
+zcat -f /var/log/nginx/access.log* > /var/log/nginx/access-all.log
+```
+
+**Set up Redis server**
+
+```bash
+sudo apt install redis-server redis-tools
+
+# check if server is running
+sudo service redis status
+
+# set and get a key value
+redis-cli set mykey myvalue
+redis-cli get mykey
+
+# interactive shell
+redis-cli
+```
+
+**Generate statistics of your webserver**
+
+```bash
+sudo apt install goaccess
+
+# check if installed
+goaccess -v
+
+# combine logs
+zcat -f /var/log/nginx/access.log* > /var/log/nginx/access-all.log
+
+# export to single html
+goaccess \
+  --log-file=/var/log/nginx/access-all.log \
+  --log-format=COMBINED \
+  --exclude-ip=0.0.0.0 \
+  --ignore-crawlers \
+  --real-os \
+  --output=/var/www/html/stats.html
+
+# cleanup afterwards
+rm /var/log/nginx/access-all.log
+```
+
+**Search for a given pattern in files**
+
+```bash
+grep -r ‘pattern’ files
+```
+
+**Find proccess ID for a specific program**
+
+```bash
+pgrep nginx
+```
+
+**Print name of current/working directory**
+
+```bash
+pwd
+```
+
+**Creates a blank new file**
+
+```bash
+touch newfile.txt
+```
+
+**Displays first lines in a file**
+
+```bash
+# -n <x> presents the number of lines (10 by default)
+head -n 20 somefile.txt
+```
+
+**Displays last lines in a file**
+
+```bash
+# -n <x> presents the number of lines (10 by default)
+tail -n 20 somefile.txt
+
+# -f follows the changes in file (doesn't closes)
+tail -f somefile.txt
+```
+
+**Count lines in a file**
+
+```bash
+wc -l somefile.txt
+```
+
+**Find all instances of the file**
+
+```bash
+sudo apt install mlocate
+
+locate somefile.txt
+```
+
+**Find file names that begin with ‘index’ in /home folder**
+
+```bash
+find /home/ -name "index"
+```
+
+**Find files larger than 100MB in the home folder**
+
+```bash
+find /home -size +100M
+```
+
+**Displays block devices related information**
+
+```bash
+lsblk
+```
+
+**Displays free space on mounted systems**
+
+```bash
+df -h
+```
+
+**Displays free and used memory in the system**
+
+```bash
+free -h
+```
+
+**Displays all active listening ports**
+
+```bash
+sudo apt install net-tools
+
+netstat -pnltu
+```
+
+**Kill a process violently**
+
+```bash
+kill -9 <pid>
+```
+
+**List files opened by user**
+
+```bash
+lsof -u <user>
+```
+
+**Execute "df -h", showing periodic updates**
+
+```bash
+# -n 1 means every second
+watch -n 1 df -h
+```
+
diff --git a/_posts/posts/2021-12-03-debian-based-riced-up-distribution-for-developers.md b/_posts/posts/2021-12-03-debian-based-riced-up-distribution-for-developers.md
new file mode 100644
index 0000000..4f9bc09
--- /dev/null
+++ b/_posts/posts/2021-12-03-debian-based-riced-up-distribution-for-developers.md
@@ -0,0 +1,277 @@
+---
+title: Debian based riced up distribution for Developers and DevOps folks
+permalink: /debian-based-riced-up-distribution-for-developers-and-devops-folks.html
+date: 2021-12-03T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Introduction
+
+I have been using [Ubuntu](https://ubuntu.com/) for quite a longtime now. I have
+used [Debian](https://www.debian.org/) in the past and
+[Manjaro](https://manjaro.org/).  Also had [Arch](https://archlinux.org/) for
+some time and even ran [Gentoo](https://www.gentoo.org/) way back.
+
+What I learned from all this is that I prefer running a bit older versions and
+having them be stable than run bleeding edge rolling release. For that reason, I
+stuck with Ubuntu for a couple of years now. I am also at a point in my life
+where I just don't care what is cool or hip anymore. I just want a stable system
+that doesn't get in my way.
+
+During all this, I noticed that these distributions were getting very bloated
+and a lot of software got included that I usually uninstall on fresh
+installation. Maybe this is my OCD speaking, but why do I have to give fresh
+installation min 1 GB of ram out of the box just to have a blank screen in front
+of me? I get it, there are many things included in the distro to make my life
+easier. I understand. But at this point I have a feeling that modern Linux
+distributions are becoming similar to [Node.js project with
+node_modules](https://devhumor.com/content/uploads/images/August2017/node-modules.jpg).
+Just a crazy number of packages serving very little or no purpose, just
+supporting other software.
+
+I felt I needed a fresh start. To start over with something minimal and clean.
+Something that would put a little more joy into using a computer again.
+
+For the first version, I wanted to target the following machines I have at home
+that I want this thing to work on.
+
+```yaml
+# My main stationary work machine
+Resolution: 3840x1080 (Super Ultrawide Monitor 32:9)
+CPU: Intel i7-8700 (12) @ 4.600GHz
+GPU: AMD ATI Radeon RX 470/480/570/570X/580/580X/590
+Memory: 32020MiB
+```
+
+```yaml
+# Thinkpad x220 for testing things and goofing around
+Resolution: 1366x768
+CPU: Intel i5-2520M (4) @ 3.200GHz
+GPU: Intel 2nd Generation Core Processor Family
+Memory: 15891MiB
+```
+
+## How should I approach this?
+
+I knew I wanted to use [minimal Debian netinst
+](https://www.debian.org/CD/netinst/) for the base to give myself a head
+start. No reason to go through changing the installer and also testing all that
+behemoth of a thing. So, some sort of ricing was the only logical option to get
+this thing of the grounds somewhat quickly.
+
+> **What is ricing anyway?**
+> The term “RICE” stands for Race Inspired Cosmetic Enhancement. A group of 
+> people (could be one, idk) decided to see if they could tweak their own 
+> distros like they/others did their cars. This gave rise to a community of
+> Linux/Unix enthusiasts trying to make their distros look cooler and better 
+> than others... For more information, read this article 
+> [What in the world is ricing!?](https://pesos.github.io/2020/07/14/what-is-ricing.html).
+
+I didn't want this to just be a set of config files for theming purpose. I
+wanted this to include a set of pre-installed tools and services that are being
+used all the time by a modern developer. Theming is just a tiny part of it.
+Fonts being applied across the distro and things like that.
+
+First, I choose terminal installer and left it to load additional components.
+Avoid using graphical installer in this case.
+
+![](/assets/posts/dfd-rice/install-00.png){:loading="lazy"}
+
+After that I selected hostname and created a normal user and set password for
+that user and root user and choose guided mode for disk partitioning.
+
+![](/assets/posts/dfd-rice/install-01.png){:loading="lazy"}
+
+I left it run to install all the things required for the base system and opted
+out of scanning additional media for use by the package manager. Those will be
+downloaded from the internet during installation.
+
+![](/assets/posts/dfd-rice/install-02.png){:loading="lazy"}
+
+I opted out of the popularity contest, and **now comes the important part**.
+Uncheck all the boxes in Software selection and only leave 'standard system
+utilities'. I also left an SSH server, so I was able to log in to the machine
+from my main PC.
+
+![](/assets/posts/dfd-rice/install-03.png){:loading="lazy"}
+
+At this point, I installed GRUB bootloader on the disk where I installed the
+system.
+
+![](/assets/posts/dfd-rice/install-04.png){:loading="lazy"}
+
+That concluded the installation of base Debian and after restarting the computer
+I was prompted with the login screen.
+
+![](/assets/posts/dfd-rice/install-05.png){:loading="lazy"}
+
+Now that I had the base installation, it was time to choose what software do I
+want to include in this so-called distribution. I wanted out of the box
+developer experience, so I had plenty to choose.
+
+Let's not waste time and go through the list.
+
+## Desktop environments
+
+I have been using [Gnome](https://www.gnome.org/) for my whole Linux life.  From
+version 2 forward. It's been quite a ride. I hated version 3 when it came out
+and replaced version 2. But I got used to it. And now with version 40+ they also
+made couple of changes which I found both frustrating and presently surprised.
+
+The amount of vertical space you loose because of the beefy title bars on
+windows is ridiculous. And then in case of
+[Tilix](https://gnunn1.github.io/tilix-web/) you also have tabs, and you are
+100px deep. Vertical space is one of the most important things for a
+developer. The more real estate you have, the more code you can have in a
+viewport.
+
+But on the other hand, I still love how Gnome feels and looks. I gotta give them
+that. They really are trying to make Gnome feel unified and modern.
+
+Regardless of all the nice things Gnome has, I was looking at the tiling window
+managers for some time, but never had the nerve to actually go with it. But now
+was the ideal time to give it a go. No guts, no glory kind of a thing.
+
+One of the requirements for me was easy custom layouts because I use a really
+strange monitor with aspect ratio of 32:9. So relying on included layouts most
+of them have is a non-starter.
+
+What I was doing in Gnome was having windows in a layout like the diagram
+below. This is my common practice. And if you look at it you can clearly see I
+was replicating tiling window manager setup in Gnome.
+
+![](/assets/posts/dfd-rice/layout.png){:loading="lazy"}
+
+That made me look into a bunch of tiling window managers and then tested them
+out. Candidates I was looking at were:
+
+- [i3](https://i3wm.org/)
+- [bspwm](https://github.com/baskerville/bspwm)
+- [awesome](https://awesomewm.org/index.html)
+- [XMonad](https://xmonad.org/)
+- [sway](https://swaywm.org/)
+- [Qtile](http://www.qtile.org/)
+- [dwm](https://dwm.suckless.org/)
+
+You can also check article [13 Best Tiling Window Managers for
+Linux](https://www.tecmint.com/best-tiling-window-managers-for-linux/) I was
+referencing while testing them out.
+
+While all of them provided what I needed, I liked i3 the most. What particular
+caught my eye was the ease to use and tree based layouts which allows flexible
+layouts. I know others can be set up also to have custom layouts other than  
+spiral, dwindle etc. I think i3 is a good entry-level window manager for 
+somebody like me.
+
+## Batteries included
+
+The source for the whole thing is located on Github
+https://github.com/mitjafelicijan/dfd-rice.
+
+Currenly included:
+
+- `non-free` (enables non-free packages in apt)
+- `sudo` (adds sudo and adds user to sudo group)
+- `essentials` (gcc, htop, zip, curl, etc...)
+- `wifi` (network manager nmtui)
+- `desktop` (i3, dmenu, fonts, configurations)
+- `pulseaudio` (pulseaudio with pavucontrol)
+- `code-editors` (vim, micro, vscode)
+- `ohmybash` (make bash pretty)
+- `file-managers` (mc)
+- `git-ui` (terminal git gui)
+- `meld` (diff tool)
+- `profiling` (kcachegrind, valgrind, strace, ltrace)
+- `browsers` (brave, firefox, chromium)
+- programming languages:
+  - `python`
+  - `golang`
+  - `nodejs`
+  - `rust`
+  - `nim`
+  - `php`
+  - `ruby`
+- `docker` (with docker-compose)
+- `ansible`
+
+Install script also allows you to install only specific packages (example for:
+essentials ohmybash docker rust).
+
+```sh
+su - root \
+    bash -c "$(wget -q https://raw.github.com/mitjafelicijan/dfd-rice/master/tools/install.sh -O -)" -- \
+    essentials ohmybash docker rust
+```
+
+Currently, most of these recipes use what Debian and this is totally fine with
+me since I never use bleeding edge features of a package. But if something major
+would come to light, I will replace it with a possible compilation script or
+something similar.
+
+This is some of the output from the installation script.
+
+![](/assets/posts/dfd-rice/script.png){:loading="lazy"}
+
+Let's take a look at some examples in the installation script.
+
+### Docker recipe
+
+```sh
+# docker
+print_header "Installing Docker"
+curl -fsSL https://download.docker.com/linux/debian/gpg | gpg --yes --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg
+echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/debian $(lsb_release -cs) stable" | tee /etc/apt/sources.list.d/docker.list > /dev/null
+apt update
+apt -y install docker-ce docker-ce-cli containerd.io docker-compose
+
+systemctl start docker
+systemctl enable docker
+systemctl status docker --no-pager
+
+/sbin/usermod -aG docker $USERNAME
+```
+
+### Making bash pretty
+
+I really like [Oh My Zsh](https://ohmyz.sh/), but I don't like zsh shell.  When
+I used it, I constantly needed to be aware of it and running bash scripts was a
+pain. So, I was really delighted when I found out that a version for bash
+existed called [Oh My Bash](https://ohmybash.nntoan.com/). Let's take a look at
+the recipe for installing it.
+
+```sh
+# ohmybash
+print_header "Enabling OhMyBash"
+sudo -u $USERNAME sh -c "$(curl -fsSL https://raw.github.com/ohmybash/oh-my-bash/master/tools/install.sh)" &
+T1=${!}
+wait ${T1}
+```
+
+Because OhMyBash does `exec bash` at the end, this traps our script inside
+another shell and our script cannot continue.  For that reason, I executed this
+in background. But that presents a new problem. Because this is executed in
+background, we lose track of progress naturally. And that strange trick with
+`T1=${!}` and `wait ${T1}` waits for the background process to finish before
+continuing to another task in bash script.
+
+Check [Multi-Threaded Processing in Bash Scripts](https://www.cloudsavvyit.com/12277/how-to-use-multi-threaded-processing-in-bash-scripts/)
+for more details.
+
+## Conclusion
+
+Take a look at
+https://github.com/mitjafelicijan/dfd-rice/blob/develop/tools/install.sh script
+to get familiar with it. This is just a first iteration and I will continue to
+update it because I need this in my life.
+
+The current version boots in 4s to the login prompt, and after you log in, the
+desktop environment loads in 2s. So, its fast, very fast. And on clean boot, I
+measured ~230 MB of RAM usage.
+
+And this is how it looks with two terminals side by side. I really like the
+simplicity and clean interface. I will polish the colors and stuff like that,
+but I really do like the results.
+
+![](/assets/posts/dfd-rice/desktop.png){:loading="lazy"}
diff --git a/_posts/posts/2021-12-25-running-golang-application-as-pid1.md b/_posts/posts/2021-12-25-running-golang-application-as-pid1.md
new file mode 100644
index 0000000..edd5a57
--- /dev/null
+++ b/_posts/posts/2021-12-25-running-golang-application-as-pid1.md
@@ -0,0 +1,348 @@
+---
+title: Running Golang application as PID 1 with Linux kernel
+permalink: /running-golang-application-as-pid1.html
+date: 2021-12-25T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Unikernels, kernels, and alike
+
+I have been reading a lot about
+[unikernernels](https://en.wikipedia.org/wiki/Unikernel) lately and found them
+very intriguing. When you push away all the marketing speak and look at the
+idea, it makes a lot of sense.
+
+> A unikernel is a specialized, single address space machine image constructed
+> by using library operating systems. ([Wikipedia](https://en.wikipedia.org/wiki/Unikernel))
+
+I really like the explanation from the article
+[Unikernels: Rise of the Virtual Library Operating System](https://queue.acm.org/detail.cfm?id=2566628).
+Really worth a read.
+
+If we compare a normal operating system to a unikernel side by side, they would
+look something like this.
+
+![Virtual machines vs Containers vs Unikernels](/assets/posts/pid1/unikernels.webp){:loading="lazy"}
+
+From this image, we can see how the complexity significantly decreases with
+the use of Unikernels. This comes with a price, of course. Unikernels are hard
+to get running and require a lot of work since you don't have an actual proper
+kernel running in the background providing network access and drivers etc.
+
+So as a half step to make the stack simpler, I started looking into using
+Linux kernel as a base and going from there. I came across this
+[Youtube video talking about Building the Simplest Possible Linux System](https://www.youtube.com/watch?v=Sk9TatW9ino)
+by [Rob Landley](https://landley.net) and apart from statically compiling the
+application to be run as PID1 there was really no other obstacles.
+
+## What is PID 1?
+
+PID 1 is the first process that Linux kernel starts after the boot process.
+It also has a couple of unique properties that are unique to it.
+
+- When the process with PID 1 dies for any reason, all other processes are
+  killed with KILL signal.
+- When any process having children dies for any reason, its children are
+  re-parented to process with PID 1.
+- Many signals which have default action of Term do not have one for PID 1.
+- When the process with PID 1 dies for any reason, kernel panics, which
+  result in system crash.
+
+PID 1 is considered as an Init application which takes care of running other
+and handling services like:
+
+- sshd,
+- nginx,
+- pulseaudio,
+- etc.
+
+If you are on a Linux machine, you can check what your process is with PID 1
+by running the following.
+
+```sh
+$ cat /proc/1/status
+Name:   systemd
+Umask:  0000
+State:  S (sleeping)
+Tgid:   1
+Ngid:   0
+Pid:    1
+PPid:   0
+...
+```
+
+As we can see on my machine the process with id of 1 is [systemd](https://systemd.io/)
+which is a software suite that provides an array of system components for Linux
+operating systems. If you look closely you can also see that the `PPid`
+(process id of the parent process) is `0` which additionally confirms that
+this process doesn't have a parent.
+
+## So why even run application as PID 1 instead of just using a container?
+
+Containers are wonderful, but they come with a lot of baggage. And because they
+are in their nature layered, the images require quite a lot of space and also a
+lot of additional software to handle them. They are not as lightweight as they
+seem, and many popular images require 500 MB plus disk space.
+
+The idea of running this as PID 1 would result in a significantly smaller footprint,
+as we will see later in the post.
+
+> You could run a simple init system inside Docker container described more
+> in this article [Docker and the PID 1 zombie reaping problem](https://blog.phusion.nl/2015/01/20/docker-and-the-pid-1-zombie-reaping-problem/).
+
+## The master plan
+
+1. Compile Linux kernel with the default definitions.
+2. Prepare a Hello World application in Golang that is statically compiled.
+3. Run it with [QEMU](https://www.qemu.org/) and providing Golang application
+   as init application / PID 1.
+
+For the sake of simplicity we will not be cross-compiling any of it and just
+use the 64bit version.
+
+## Compiling Linux kernel
+
+```sh
+$ wget https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.15.7.tar.xz
+$ tar xf linux-5.15.7.tar.xz
+
+$ cd linux-5.15.7
+
+$ make clean
+
+# read more about this https://stackoverflow.com/a/41886394
+$ make defconfig
+
+$ time make -j `nproc`
+
+$ cd ..
+```
+
+At this point we have kernel image that is located in `arch/x86_64/boot/bzImage`.
+We will use this in QEMU later.
+
+To make our lives a bit easier lets move the kernel image to another place.
+Lets create a folder `bin/` in the root of our project with `mkdir -p bin`.
+
+
+At this point we can copy `bzImage` to `bin/` folder with
+`cp linux-5.15.7/arch/x86_64/boot/bzImage bin/bzImage`.
+
+The folder structure of this experiment should look like this.
+
+```txt
+pid1/
+  bin/
+    bzImage
+  linux-5.15.7/
+  linux-5.15.7.tar.xz
+```
+
+## Preparing PID 1 application in Golang
+
+This step is relatively easy. The only thing we must have in mind that we will
+need to compile the binary as a static one.
+
+Let's create `init.go` file in the root of the project.
+
+```go
+package main
+
+import (
+  "fmt"
+  "time"
+)
+
+func main() {
+  for {
+    fmt.Println("Hello from Golang")
+    time.Sleep(1 * time.Second)
+  }
+}
+```
+
+If you notice, we have a forever loop in the main, with a simple sleep of 1
+second to not overwhelm the CPU. This is because PID 1 should never complete
+and/or exit. That would result in a kernel panic. Which is BAD!
+
+There are two ways of compiling Golang application. Statically and dynamically.
+
+To statically compile the binary, use the following command.
+
+```sh
+$ go build -ldflags="-extldflags=-static" init.go
+```
+
+We can also check if the binary is statically compiled with:
+
+```sh
+$ file init
+init: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, Go BuildID=Ypu8Zw_4NBxm1Yxg2OYO/H5x721rQ9uTPiDVh-VqP/vZN7kXfGG1zhX_qdHMgH/9vBfmK81tFrygfOXDEOo, not stripped
+
+$ ldd init
+not a dynamic executable
+```
+
+At this point, we need to create [initramfs](https://www.linuxfromscratch.org/blfs/view/svn/postlfs/initramfs.html)
+(abbreviated from "initial RAM file system", is the successor of initrd. It
+is a cpio archive of the initial file system that gets loaded into memory
+during the Linux startup process).
+
+```sh
+$ echo init | cpio -o --format=newc > initramfs
+$ mv initramfs bin/initramfs
+```
+
+The projects at this stage should look like this.
+
+```txt
+pid1/
+  bin/
+    bzImage
+    initramfs
+  linux-5.15.7/
+  linux-5.15.7.tar.xz
+  init.go
+```
+
+## Running all of it with QEMU
+
+[QEMU](https://www.qemu.org/) is a free and open-source hypervisor. It emulates
+the machine's processor through dynamic binary translation and provides a set
+of different hardware and device models for the machine, enabling it to run a
+variety of guest operating systems.
+
+```sh
+$ qemu-system-x86_64 -serial stdio -kernel bin/bzImage -initrd bin/initramfs -append "console=ttyS0" -m 128
+```
+
+```sh
+$ qemu-system-x86_64 -serial stdio -kernel bin/bzImage -initrd bin/initramfs -append "console=ttyS0" -m 128
+[    0.000000] Linux version 5.15.7 (m@khan) (gcc (GCC) 11.2.1 20211203 (Red Hat 11.2.1-7), GNU ld version 2.37-10.fc35) #7 SMP Mon Dec 13 10:23:25 CET 2021
+[    0.000000] Command line: console=ttyS0
+[    0.000000] x86/fpu: x87 FPU will use FXSAVE
+[    0.000000] signal: max sigframe size: 1440
+[    0.000000] BIOS-provided physical RAM map:
+[    0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
+[    0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
+[    0.000000] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved
+[    0.000000] BIOS-e820: [mem 0x0000000000100000-0x0000000007fdffff] usable
+[    0.000000] BIOS-e820: [mem 0x0000000007fe0000-0x0000000007ffffff] reserved
+[    0.000000] BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved
+[    0.000000] NX (Execute Disable) protection: active
+[    0.000000] SMBIOS 2.8 present.
+[    0.000000] DMI: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-6.fc35 04/01/2014
+[    0.000000] tsc: Fast TSC calibration failed
+...
+[    2.016106] ALSA device list:
+[    2.016329]   No soundcards found.
+[    2.053176] Freeing unused kernel image (initmem) memory: 1368K
+[    2.056095] Write protecting the kernel read-only data: 20480k
+[    2.058248] Freeing unused kernel image (text/rodata gap) memory: 2032K
+[    2.058811] Freeing unused kernel image (rodata/data gap) memory: 500K
+[    2.059164] Run /init as init process
+Hello from Golang
+[    2.386879] tsc: Refined TSC clocksource calibration: 3192.032 MHz
+[    2.387114] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x2e02e31fa14, max_idle_ns: 440795264947 ns
+[    2.387380] clocksource: Switched to clocksource tsc
+[    2.587895] input: ImExPS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input3
+Hello from Golang
+Hello from Golang
+Hello from Golang
+```
+
+The whole [log file here](/assets/posts/pid1/qemu.log).
+
+## Size comparison
+
+The cool thing about this approach is that the Linux kernel and the application
+together only take around 12 MB, which is impressive as hell. And we need to
+also know that the size of bzImage (Linux kernel) could be greatly decreased
+by going into `make menuconfig` and removing a ton of features from the kernel,
+making the size even smaller. I managed to get kernel size down to 2 MB and
+still working properly.
+
+```sh
+total 12M
+-rw-r--r--. 1 m m 9.3M Dec 13 10:24 bzImage
+-rw-r--r--. 1 m m 1.9M Dec 27 01:19 initramfs
+```
+
+## Creating ISO image and running it with Gnome Boxes
+
+First we need to create proper folder structure with `mkdir -p iso/boot/grub`.
+
+Then we need to download the [grub binary](https://github.com/littleosbook/littleosbook/raw/master/files/stage2_eltorito).
+You can read more about this program on https://github.com/littleosbook/littleosbook.
+
+```sh
+$ wget -O iso/boot/grub/stage2_eltorito https://github.com/littleosbook/littleosbook/raw/master/files/stage2_eltorito
+```
+
+```sh
+$ tree iso/boot/
+iso/boot/
+├── bzImage
+├── grub
+│   ├── menu.lst
+│   └── stage2_eltorito
+└── initramfs
+```
+
+Let's copy files into proper folders.
+
+
+```sh
+$ cp stage2_eltorito iso/boot/grub/
+$ cp bin/bzImage iso/boot/
+$ cp bin/initramfs iso/boot/
+```
+
+Lets create a GRUB config file at `nano iso/boot/grub/menu.lst` with contents.
+
+```ini
+default=0
+timeout=5
+
+title GoAsPID1
+kernel /boot/bzImage
+initrd /boot/initramfs
+```
+
+Let's create iso file by using genisoimage:
+
+```sh
+genisoimage -R                              \
+            -b boot/grub/stage2_eltorito    \
+            -no-emul-boot                   \
+            -boot-load-size 4               \
+            -A os                           \
+            -input-charset utf8             \
+            -quiet                          \
+            -boot-info-table                \
+            -o GoAsPID1.iso                 \
+            iso
+```
+
+This will produce `GoAsPID1.iso` which you can use with [Virtualbox](https://www.virtualbox.org/)
+or [Gnome Boxes](https://apps.gnome.org/app/org.gnome.Boxes/).
+
+<video src="/assets/posts/pid1/boxes.mp4" controls></video>
+
+## Is running applications as PID 1 even worth it?
+
+Well, the answer to this is not as simple as one would think. Sometimes it is
+and sometimes it's not. For embedded systems and very specialized applications
+it is worth for sure. But in normal uses, I don't think so. It was an interesting
+exercise in compiling kernels and looking at the guts of the Linux kernel,
+but sticking to containers for most of the things is a better option in my
+opinion.
+
+An interesting experiment would be creating an image that supports networking
+and could be deployed to AWS as an EC2 instance and observing how it fares.
+But in that case, we would need to write some sort of supervisor that would
+run on a separate EC2 that would check if other EC2 instances are running
+properly. Remember that if your application fails, kernel panics and the
+whole machine is inoperable in this case.
diff --git a/_posts/posts/2021-12-30-wap-mobile-web-before-the-web.md b/_posts/posts/2021-12-30-wap-mobile-web-before-the-web.md
new file mode 100644
index 0000000..665be0f
--- /dev/null
+++ b/_posts/posts/2021-12-30-wap-mobile-web-before-the-web.md
@@ -0,0 +1,203 @@
+---
+title: Wireless Application Protocol and the mobile web before the web
+permalink: /wap-mobile-web-before-the-web.html
+date: 2021-12-30T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## A little stroll down the history lane
+
+About two weeks ago, I watched this outstanding documentary on YouTube
+[Springboard: the secret history of the first real
+smartphone](https://www.youtube.com/watch?v=b9_Vh9h3Ohw) about the history of
+smartphones and phones in general. It brought back so many memories. I never had
+an actual smartphone before the Android. The closest to smartphone was [Sony
+Ericsson P1](https://www.gsmarena.com/sony_ericsson_p1-1982.php).  A fantastic
+phone and I broke it in Prague after a party and that was one of those rare
+occasions where I was actually mad at myself. But nevertheless, after that
+phone, the next one was an Android one.
+
+Before that, I only owned normal phones from Nokia and Siemens etc. Nothing
+special, actually. These are the phones we are talking about. Before 2007.
+Apple and Android phones didn't exist yet.
+
+These phones were rocking:
+
+- No selfie cameras.
+- ~2 inch displays.
+- ~120 MHz beast CPU's.
+- 144p main cameras.
+- But they had a headphone jack.
+
+Let's take a look at these beauties.
+
+![Old phones](/assets/posts/wap/phones.gif){:loading="lazy"}
+
+## WAP - Wireless Application Protocol
+
+Not that one! We are talking about Wireless Application Protocol and not Cardi
+B's song 😃
+
+WAP stands for Wireless Application Protocol. It is a protocol designed for
+micro-browsers, and it enables the access of internet in the mobile devices.  It
+uses the mark-up language WML (Wireless Markup Language and not HTML), WML is
+defined as XML 1.0 application. Furthermore, it enables creating web
+applications for mobile devices. In 1998, WAP Forum was founded by Ericson,
+Motorola, Nokia and Unwired Planet whose aim was to standardize the various
+wireless technologies via protocols.
+[(source)](https://www.geeksforgeeks.org/wireless-application-protocol/)
+
+WAP protocol was resulted by the joint efforts of the various members of WAP
+Forum. In 2002, WAP forum was merged with various other forums of the industry,
+resulting in the formation of Open Mobile Alliance (OMA).
+[(source)](https://www.geeksforgeeks.org/wireless-application-protocol/)
+
+These were some wild times. Devices had tiny screens and data transmission rates
+were abominable. But they were capable of rendering WML (Wireless Markup
+Language). This was very similar to HTML, actually. It is a markup language,
+after all.
+
+These pages could be served by [Apache](https://apache.org/) and could be
+generated by CGI scripts on the backend. The only difference was the limited
+markup language.
+
+## WML - Wireless Markup Language
+
+Just like web browsers use HTML for content structure, older mobile device
+browsers use WML - if you need to support really old mobile phones using WML
+browsers, you will need to know about it. WML is XML-based (an XML vocabulary
+just like XHTML and MathML, but not HTML) and does not use the same metaphor as
+HTML. HTML is a single document with some metadata packed away in the head, and
+a body encapsulating the visible page. With WML, the metaphor does not envisage
+a page, but rather a deck of cards. A WML file might have several pages or cards
+contained within it.
+[(source)](https://www.w3.org/wiki/Introduction_to_mobile_web)
+
+```html
+<?xml version="1.0"?>
+<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.wapforum.org/DTD/wml_1.1.xml">
+<wml>
+  <card id="home" title="Example Homepage">
+    <p>Welcome to the Example homepage</p>
+  </card>
+</wml>
+```
+
+There is an amazing tutorial on [Tutorialpoint about
+WML](https://www.tutorialspoint.com/wml/index.htm).
+
+## Converting Digg to WML
+
+This task is completely useless and not really feasible nowadays, but I had to
+give it a try for old-time sake. Since the data is already there in a form of
+RSS feed, I could take this feed and parse it and create a WML version of the
+homepage.
+
+We will need:
+
+- Python3 + Pip
+- ImageMagick
+- feedparser and mako templating
+
+```sh
+# for fedora 35
+sudo dnf install ImageMagick python3-pip
+
+# tempalting engine for python
+pip install mako --user
+
+# for parsing rss feeds
+pip install feedparser --user
+```
+
+Project folder structure should look like the following.
+
+```
+12:43:53 m@khan wap → tree -L 1
+.
+├── generate.py
+└── template.wml
+
+```
+
+After that, I created a small template for the homepage.
+
+```html
+<?xml version="1.0"?>
+<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.2//EN" "http://www.wapforum.org/DTD/wml_1.2.xml">
+
+<wml>
+
+  <card title="Digg - What the Internet is talking about right now">
+
+    % for item in entries:
+      <p><img src="/images/${item.id}.jpg" width="175" height="95" alt="${item.title}" /></p>
+      <p><small>${item.kicker}</small></p>
+      <p><big><b>${item.title}</b></big></p>
+      <p>${item.description}</p>
+    % endfor
+
+  </card>
+
+</wml>
+```
+
+And the parser that parses RSS feed looks like this.
+
+```python
+import os
+import feedparser
+from mako.template import Template
+
+os.system('mkdir -p www/images')
+
+template = Template(filename='template.wml')
+
+feed = feedparser.parse('https://digg.com/rss/top.xml')
+
+entries = feed.entries[:15]
+
+for entry in entries:
+  print('Processing image with id {}'.format(entry.id))
+  os.system('wget -q -O www/images/{}.jpg "{}"'.format(entry.id, entry.links[1].href))
+  os.system('convert www/images/{}.jpg -type Grayscale -resize 175x -depth 3 -quality 30 www/images/{}.jpg'.format(entry.id, entry.id))
+
+html = template.render(entries = entries)
+
+with open('www/index.wml', 'w+') as fp:
+  fp.write(html)
+```
+
+This script will create a folder `www` and in the folder `www/images` for
+storing resized images.
+
+> Be sure you don't use SSL and use just normal HTTP for serving the content.
+> These old phones will have problems with TLS 1.3 etc.
+
+If you look at the python file, I convert all the images into tiny B&W images.
+They should be WBMP (Wireless BitMaP) but I choose JPEGs for this, and it seems
+to work properly.
+
+Because I currently don't have a phone old enough to test it on, I used an
+emulator. And it was really hard to find one. I found [WAP
+Proof](http://wap-proof.sharewarejunction.com/) on shareware junction, and it
+did the job well enough. I will try to find and actual device to test it on.
+
+<video src="/assets/posts/wap/emulator.mp4" controls></video>
+
+If you are using Nginx to serve the contents, add a directive to the hosts file
+that will automatically server `index.wml` file.
+
+```nginx
+server {
+  index index.wml index.html index.htm index.nginx-debian.html;
+}
+```
+
+## Conclusion
+
+Well, this was pointless, but very fun! I hope you enjoyed it as much as I did.
+I will try to find an old phone to test it on. If you have any questions, feel
+free to ask in the comments.
diff --git a/_posts/posts/2022-06-30-trying-out-helix-editor.md b/_posts/posts/2022-06-30-trying-out-helix-editor.md
new file mode 100644
index 0000000..be369a1
--- /dev/null
+++ b/_posts/posts/2022-06-30-trying-out-helix-editor.md
@@ -0,0 +1,55 @@
+---
+title: Trying out Helix code editor as my main editor
+permalink: /tying-out-helix-code-editor.html
+date: 2022-06-30T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+I have been searching for a lightweight code editor for quite some time. One of
+the main reasons was that I wanted something that doesn't burn through CPU and
+RAM usage is not through the roof. I have been mostly using Visual Studio Code.
+It's been an outstanding editor. I have no quarrel with it at all. It's just
+time to spice life up with something new.
+
+I have been on this search for a couple of years. I have tried Vim, Neovim,
+Emacs, Doom Emacs, Micro and couple more. Among most of them, I liked Micro and
+Doom Emacs the most. Micro editor was a little too basic for me. And Doom Emacs
+was a bit too hardcore. This does not reflect on any of the editors. It's just
+my personal preference.
+
+> I tried Helix Editor about a year ago. But I didn't pay attention to it.
+> Tried it and saw it's similar to Vi and just said no. I was premature to
+> dismiss it.
+
+One of the things I actually miss is line wrapping for certain files. When
+writing Markdown, line wrapping would be very helpful. Editing such a document
+is frustrating to say the least. Some of the Markdown to HTML converters don't
+take kindly of new lines between sentences. Not paragraphs, sentences. And I use
+Markdown to write this blog you are reading.
+
+But other than this, I have been extremely satisfied by it. It's been a pleasant
+surprise. There have been zero issues with the editor.
+
+One thing to do before you are able to use autocompletion and make use Language
+Server support is to install the language server with NPM.
+
+```sh
+# For C development this installs C LSP.
+sudo dnf install clang-tools-extra
+```
+
+I am still getting used to the keyboard shortcuts and getting better. What Helix
+does really well is packing in sane defaults and even though because currently
+there is no plugin support I haven't found any need for them. It has all that
+you would need. It goes to extreme measures to show a user what is going on with
+popups that show you what the keyboard shortcuts are.
+
+And it comes us packed with many
+[really good themes](https://github.com/helix-editor/helix/wiki/Themes).
+
+![Editor](/assets/posts/helix-editor/editor.png){:loading="lazy"}
+
+It's still young but has this mature feeling to it. It has sane defaults and
+mimics Vim (works a bit differently, but the overall idea is similar).
diff --git a/_posts/posts/2022-07-05-what-would-dna-sound-if-synthesized.md b/_posts/posts/2022-07-05-what-would-dna-sound-if-synthesized.md
new file mode 100644
index 0000000..6efe559
--- /dev/null
+++ b/_posts/posts/2022-07-05-what-would-dna-sound-if-synthesized.md
@@ -0,0 +1,365 @@
+---
+title: What would DNA sound if synthesized to an audio file
+permalink: /what-would-dna-sound-if-synthesized.html
+date: 2022-07-05T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Introduction
+
+Lately, I have been thinking a lot about the nature of life, what are the
+foundation blocks of life and things like that. It's remarkable how complex and
+on the other hand simple the creation is when you look at it. The miracle of
+life keeps us grounded when our imagination goes wild. If the DNA are the blocks
+of life, you could consider them to be an API nature provided us to better
+understand all of this chaos masquerading as order.
+
+I have been reading a lot about superintelligence and our somehow misguided path
+to create general artificial intelligence. What would the building blocks or our
+creation look like? Is the compression really the ultimate storage of
+information? Will our creation also ponder this questions when creating new
+worlds for themselves, or will we just disappear into the vastness of
+possibilities? It is a little offensive that we are playing God whilst being
+completely ignorant of our own reality. Who knows! Like many other
+breakthroughs, this one will also come at a cost not known to us when it finally
+happens.
+
+To keep things a bit lighter, I decided to convert some popular DNA sequences
+into an audio files for us to listen to. I am not the first one, nor I will be
+the last one to do this. But it is an interesting exercise in better
+understanding the relationship between art and science. Maybe listening to DNA
+instead of parsing it will find a way into better understanding, or at least
+enjoying the creation and cryptic nature of life.
+
+## DNA encoding and primer example
+
+I have been exploring DNA in the past in my post from about 3 years ago in
+[Encoding binary data into DNA
+sequence](/encoding-binary-data-into-dna-sequence.html) where I have been
+converting all sorts of data into DNA sequences.
+
+This will be a similar exercise but instead of converting to DNA, I will be
+generating tones from Nucleotides.
+
+| Nucleotides      | Note | Frequency |
+| ---------------- | ---- | --------- |
+| **A** (Adenine)  | A    | 440 Hz    |
+| **C** (Cytosine) | C    | 783.99 Hz |
+| **G** (Guanine)  | G    | 523.25 Hz |
+| **T** (Thymine)  | D    | 587.33 Hz |
+
+Since we do not have T in equal-tempered scale, I choose D to represent T note.
+
+You can check [Frequencies for equal-tempered scale, A4 = 440
+Hz](https://pages.mtu.edu/~suits/notefreqs.html).  For this tuning, we also
+choose `Speed of Sound = 345 m/s = 1130 ft/s = 770 miles/hr`.
+
+Now that we have this out of the way, we can also brush up on the DNA sequencing
+a bit. This is a famous quote I also used for the encoding tests, and it goes
+like this.
+
+> How wonderful that we have met with a paradox. Now we have some hope of
+> making progress.
+> ― Niels Bohr
+
+```shell
+>SEQ1
+GACAGCTTGTGTACAAGTGTGCTTGCTCGCGAGCGGGTACGCGCGTGGGCTAACAAGTGA
+GCCAGCAGGTGAACAAGTGTGCGGACAAGCCAGCAGGTGCGCGGACAAGCTGGCGGGTGA
+ACAAGTGTGCCGGTGAGCCAACAAGCAGACAAGTAAGCAGGTACGCAGGCGAGCTTGTCA
+ACTCACAAGATCGCTTGTGTACAAGTGTGCGGACAAGCCAGCAGGTGCGCGGACAAGTAT
+GCTTGCTGGCGGACAAGCCAGCTTGTAAGCGGACAAGCTTGCGCACAAGCTGGCAGGCCT
+GCCGGCTCGCGTACAAATTCACAAGTAAGTACGCTTGCGTGTACGCGGGTATGTATACTC
+AACCTCACCAAACGGGACAAGATCGCCGGCGGGCTAGTATACAAGAACGCTTGCCAGTAC
+AACC
+```
+
+This is what we gonna work with to get things rolling forward, when creating
+parser and waveform generator.
+
+## Parsing DNA data
+
+This step is rather simple one. All we need to do is parse input DNA sequence in
+[FASTA format](https://en.wikipedia.org/wiki/FASTA_format) well known in
+[Bioinformatics](https://en.wikipedia.org/wiki/Bioinformatics) to extract single
+Nucleotides that will be converted into separate tones based on equal-tempered
+scale explained above.
+
+```python
+nucleotide_tone_map = {
+  'A': 440,
+  'C': 523.25,
+  'G': 783.99,
+  'T': 587.33,  # converted to D
+}
+
+def split(word):
+  return [char for char in word]
+
+def generate_from_dna_sequence(sequence):
+  for nucleotide in split(sequence):
+    print(nucleotide, nucleotide_tone_map[nucleotide])
+```
+
+## Generating sine wave
+
+Because we are essentially creating a long stream of notes we will be appending
+sine notes to a global array we will later use for creating a WAV file out of
+it.
+
+```python
+import math
+
+def append_sinewave(freq=440.0, duration_milliseconds=500, volume=1.0):
+  global audio
+
+  num_samples = duration_milliseconds * (sample_rate / 1000.0)
+
+  for x in range(int(num_samples)):
+    audio.append(volume * math.sin(2 * math.pi * freq * (x / sample_rate)))
+
+  return
+```
+
+The sine wave generated here is the standard beep. If you want something more
+aggressive, you could try a square or saw tooth waveform.
+
+## Generating a WAV file from accumulated sine waves
+
+
+```python
+import wave
+import struct
+
+def save_wav(file_name):
+  wav_file = wave.open(file_name, 'w')
+  nchannels = 1
+  sampwidth = 2
+
+  nframes = len(audio)
+  comptype = 'NONE'
+  compname = 'not compressed'
+  wav_file.setparams((nchannels, sampwidth, sample_rate, nframes, comptype, compname))
+
+  for sample in audio:
+    wav_file.writeframes(struct.pack('h', int(sample * 32767.0)))
+
+  wav_file.close()
+```
+
+44100 is the industry standard sample rate - CD quality.  If you need to save on
+file size, you can adjust it downwards. The standard for low quality is, 8000 or
+8kHz.
+
+WAV files here are using short, 16 bit, signed integers for the sample size.
+So, we multiply the floating-point data we have by 32767, the maximum value for
+a short integer.
+
+> It is theoretically possible to use the floating point -1.0 to 1.0 data
+> directly in a WAV file, but not obvious how to do that using the wave module
+> in Python.
+
+## Generating Spectograms
+
+I have tried two methods of doing this and both were just fine. I however opted
+out to use the [SoX - Sound eXchange, the Swiss Army knife of audio
+manipulation](https://linux.die.net/man/1/sox) one because it didn't require
+anything else.
+
+```shell
+sox output.wav -n spectrogram -o spectrogram.png
+```
+
+An example spectrogram of Ludwig van Beethoven Symphony No. 6 First movement.
+
+<audio controls>
+  <source src="/assets/posts/dna-synthesized/symphony-no6-1st-movement.mp3" type="audio/mpeg">
+</audio>
+
+![Ludwig van Beethoven Symphony No. 6 First movement](/assets/posts/dna-synthesized/symphony-no6-1st-movement.png){:loading="lazy"}
+
+The other option could also be in combination with
+[gnuplot](http://www.gnuplot.info/).  This would require an intermediary step,
+however.
+
+```shell
+sox output.wav audio.dat
+tail -n+3 audio.dat > audio_only.dat
+gnuplot audio.gpi
+```
+
+And input file `audio.gpi` that would be passed to gnuplot looks something like
+this.
+
+```txt
+# set output format and size
+set term png size 1000,280
+
+# set output file
+set output "audio.png"
+
+# set y range
+set yr [-1:1]
+
+# we want just the data
+unset key
+unset tics
+unset border
+set lmargin 0
+set rmargin 0
+set tmargin 0
+set bmargin 0
+
+# draw rectangle to change background color
+set obj 1 rectangle behind from screen 0,0 to screen 1,1
+set obj 1 fillstyle solid 1.0 fillcolor rgbcolor "#ffffff"
+
+# draw data with foreground color
+plot "audio_only.dat" with lines lt rgb 'red'
+```
+
+## Pre-generated sequences
+
+What I did was take interesting parts from an animal's genome and feed it to a
+tone generator script. This then generated a WAV file and I converted those to
+MP3, so they can be played in a browser. The last step was creating a
+spectrogram based on a WAV file.
+
+### Niels Bohr quote
+
+<audio controls>
+  <source src="/assets/posts/dna-synthesized/quote/out.mp3" type="audio/mpeg">
+</audio>
+
+![Spectogram](/assets/posts/dna-synthesized/quote/spectogram.png){:loading="lazy"}
+
+### Mouse
+
+This is part of a mouse genome `Mus_musculus.GRCm39.dna.nonchromosomal`.  You
+can get [genom data
+here](http://ftp.ensembl.org/pub/release-106/fasta/mus_musculus/dna/).
+
+<audio controls>
+  <source src="/assets/posts/dna-synthesized/mouse/out.mp3" type="audio/mpeg">
+</audio>
+
+![Spectogram](/assets/posts/dna-synthesized/mouse/spectogram.png){:loading="lazy"}
+
+### Bison
+
+This is part of a bison genome `Bison_bison_bison.Bison_UMD1.0.cdna`.  You can
+get [genom data
+here](http://ftp.ensembl.org/pub/release-106/fasta/bison_bison_bison/cdna/).
+
+<audio controls>
+  <source src="/assets/posts/dna-synthesized/bison/out.mp3" type="audio/mpeg">
+</audio>
+
+![Spectogram](/assets/posts/dna-synthesized/bison/spectogram.png){:loading="lazy"}
+
+### Taurus
+
+This is part of a taurus genome `Bos_taurus.ARS-UCD1.2.cdna`.  You can get
+[genom data
+here](http://ftp.ensembl.org/pub/release-106/fasta/bos_taurus/cdna/).
+
+<audio controls>
+  <source src="/assets/posts/dna-synthesized/taurus/out.mp3" type="audio/mpeg">
+</audio>
+
+![Spectogram](/assets/posts/dna-synthesized/taurus/spectogram.png){:loading="lazy"}
+
+## Making a drummer out of a DNA sequence
+
+To make things even more interesting, I decided to send this data via MIDI to my
+[Elektron Model:Samples](https://www.elektron.se/en/model-samples). This is a
+really cool piece of equipment that supports MIDI in via USB and 3.5 mm audio
+jack.
+
+Elektron is connected to my MacBook via USB cable and audio out is patched to a
+Sony Bluetooth speaker I have that supports 3.5 mm audio in. Elektron doesn't
+have internal speakers.
+
+![](/assets/posts/dna-synthesized/elektron/IMG_0619.jpg){:loading="lazy"}
+
+![](/assets/posts/dna-synthesized/elektron/IMG_0620.jpg){:loading="lazy"}
+
+![](/assets/posts/dna-synthesized/elektron/IMG_0622.jpg){:loading="lazy"}
+
+For communicating with Elektron, I choose `pygame` Python module that has MIDI
+built in. With this, it was rather simple to send notes to the device. All I did
+was map MIDI notes to the actual Nucleotides.
+
+Before all of this I also checked Audio MIDI Setup app under MacOS and checked
+MIDI Studio by pressing ⌘-2.
+
+![](/assets/posts/dna-synthesized/elektron/midi-studio.jpg){:loading="lazy"}
+
+The whole script that parses and send notes to the Elektron looks like this.
+
+```python
+import pygame.midi
+import time
+
+pygame.midi.init()
+
+print(pygame.midi.get_default_output_id())
+print(pygame.midi.get_device_info(0))
+
+player = pygame.midi.Output(1)
+player.set_instrument(2)
+
+def send_note(note, velocity):
+  global player
+  player.note_on(note, velocity)
+  time.sleep(0.3)
+  player.note_off(note, velocity)
+
+
+nucleotide_midi_map = {
+  'A': 60,
+  'C': 90,
+  'G': 160,
+  'T': 180,  # is D
+}
+
+with open("quote.fa") as f:
+  sequence = f.read().replace('\n', '')
+
+for nucleotide in [char for char in sequence]:
+  print("Playing nucleotide {} with MIDI note {}".format(
+      nucleotide, nucleotide_midi_map[nucleotide]))
+  send_note(nucleotide_midi_map[nucleotide], 127)
+
+del player
+pygame.midi.quit()
+```
+
+<video src="/assets/posts/dna-synthesized/elektron/elektron.mp4" controls></video>
+
+All of this could be made much more interesting if I choose different
+instruments for different Nucleotides, or doing more funky stuff with Elektron.
+But for now, this should be enough. It is just a proof of concept. Something to
+play around with.
+
+## Going even further
+
+As you probably notice, the end results are quite similar to each other. This is
+to be expected because we are operating only with 4 notes essentially. What
+could make this more interesting is using something like
+[Supercollider](https://supercollider.github.io/) to create more interesting
+sounds. By transposing notes or using effects based on repeated data in a
+sequence. Possibilities are endless.
+
+It is really astonishing what can be achieved with a little bit of code and an
+idea. I could see this becoming an interesting background soundscape instrument
+if done properly. It could replace random note generator with something more
+intriguing, biological, natural.
+
+I actually find the results fascinating. I took some time and listened to this
+music of nature. Even though it's quite the same, it's also quite different.
+The subtle differences on repeat kind of creates music on its own. Makes you
+wonder. It kind of puts Occam’s Razor in its place. Nature for sure loves to
+make things as energy efficient as possible.
diff --git a/_posts/posts/2022-10-06-state-of-web-technologies-in-year-2022.md b/_posts/posts/2022-10-06-state-of-web-technologies-in-year-2022.md
new file mode 100644
index 0000000..e7c8d62
--- /dev/null
+++ b/_posts/posts/2022-10-06-state-of-web-technologies-in-year-2022.md
@@ -0,0 +1,297 @@
+---
+title: State of Web Technologies and Web development in year 2022
+permalink: /state-of-web-technologies-and-web-development-in-year-2022.html
+date: 2022-10-06T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+## Initial thoughts
+
+*This post is a critique on the current state of web development. It is an
+opinionated post! I will learn more about this in the future, and probably
+slightly change my mind about some of the things I criticize.*
+
+I have started working on a hobby project about two weeks ago, and I wanted to
+use that situation as a learning one. Trying new things, new technologies, new
+tools. I always considered myself to be an adventurous person when it comes to
+technology. I never shy away from trying new languages, new operating systems
+etc. Likewise, I find the whole experience satisfying, and it tickles that part
+of my brain that finds discovery the highest of the mountains to climb.
+
+What I always wanted to make was a coding game, that you would play in a browser
+(just to eliminate building binaries for each operating system) where you would
+level up your character and go into these scriptable battles. You know, RPG
+elements.
+
+So, the natural way to go would be some sort of SPA (single page application)
+with basic routing and some state management. Nothing crazy.
+
+> **Before we move on**, I have to be transparent. Take my views on this with
+> a grain of salt. I have only scratched the surface with these technologies,
+> and my knowledge is full of gaps. This is my experience using some of these
+> products for the first time or in a limited capacity.
+
+Having this out of the way, I got myself a fresh pot of coffee and down the
+rabbit hole I went.
+
+## Giving React JS a spin
+
+I first tried [React JS](https://reactjs.org/). I kind of like it. Furthermore,
+I have worked with libraries like this in the past and also wrote a couple of
+them (nothing compared to that level), but I had the basic understanding of what
+was going on. I rolled up a project quickly and had basic things done in a
+matter of two hours, which was impressive.
+
+I prefer using [Tailwind CSS](https://tailwindcss.com/) for my styling
+pleasures, and integrating that was also a painless experience. It was actually
+nice to see that some things got better with time. In about 2 minutes I got
+Tailwind working, and I was able to use classes at my disposal. All that
+`postcss` stuff was taken care of by adding a couple of things in config files
+(all described really well in their documentation).
+
+It is not that different from Vue which I have had more encounters with in the
+past People will probably call me a lunatic for saying this. But you know, it is
+the truth. Same same, but different. I still believe that using libraries like
+this is beneficial. I am not a JavaScript purist. They all have their quirks,
+but at the end of the day, I truly believe it’s worth it.
+
+## Bundlers and Transpilers
+
+I still reject calling [Typescript](https://www.typescriptlang.org/) to
+[JavaScript](https://www.javascript.com/) conversion a "compilation process".  I
+call them [transpilers](https://devopedia.org/transpiler), and I don’t care! 😈
+
+The first one that I ever used was [webpack](https://webpack.js.org/), and it
+was an absolute horrific experience. Saying this, it is an absolutely fantastic
+tool. I felt more like a config editor than actually a programmer.  To be fair,
+I am a huge fan of [make](https://www.gnu.org/software/make/), and you can do as
+you wish with this information. I like my build systems simple.
+
+Also, isn’t it interesting that we need something like
+[Babel](https://babeljs.io/) to make JavaScript code work in a browser that has
+only one client side scripting available, which is by no accident also
+JavaScript. Why? I know why it’s needed, but seriously, why.
+
+I haven’t used Babel for years now. Or if I did, it was packaged together by
+some other bundler thingy. Which does not make things better, but at least I
+didn’t need to worry about it.
+
+I really don’t like complicated build systems. I really don’t like abstracting
+code and making things appear magical. The older I get, the more I appreciate
+clear and clean, expressive code. No one-liners, if possible.
+
+But I have to give props to [Vite](https://vitejs.dev/)! This was one of the
+best developer experiences I have ever had. Granted, it still has magical
+properties. And yes, it still is a bundler and abstracts things to the nth
+degree. But at least it didn’t force me to configure 700 lines of JSON. And I
+know that this makes me a hypocrite. You can’t have it all. Nonetheless, my
+reasoning here is, if using bundlers is inevitable, then at least they should
+provide an excellent developer experience.
+
+I also noticed that now the catch-all phrase is “blazingly fast” and “lightning
+fast” and “next generation” and stuff like that. I mean, yeah, tools should get
+faster with time. But saying that starting a project now takes 2 seconds instead
+of 20 seconds is something that is a break it or make it kind of a deal is
+ridiculous. I don’t mind waiting a couple of seconds every couple of days. I
+also don’t create 700 projects every day, and also who does? This argument has
+no bite. All I want is a decent reload time (~100ms is more than good enough for
+me) and that is it.
+
+You don’t need to sell me benefits if I only get them when I start a fresh
+project, and then try to convince me that this is somehow changing the fate of
+the universe. First of all, it is not. And second, if this is your only argument
+for your tool, I would advise you to maybe re-focus your efforts to something
+else. Vite says that startup times are really fast. And if that would be the
+only thing differentiating it from other tools, I would ignore it. But it has
+some really compelling features like [Hot Module
+Replacement](https://www.geeksforgeeks.org/reactjs-hot-module-replacement/) that
+really works well. It was a joy to use.
+
+So, I will be definitely using Vite in the future.
+
+## Jam Stack, Mach Stack no snack
+
+Let's get a couple of the acronyms out of the way, so we all know what we are
+talking about:
+
+- Jam Stack - JavaScript, API and Markup
+- Mach Stack - Microservices, API-first, Cloud-Native SaaS, Headless
+
+It is so hard to follow all these new trendy things happening around you, that
+it makes you have a massive **FOMO** all the time. But on the other hand, you
+also don’t want to be that old fart that doesn’t move with the times and still
+writes his trusty jQuery code while listening to Blink 182 All the small things
+on full blast. It’s a good song, don’t get me wrong, but there are other songs
+out there.
+
+I have to admit. [Vercel](https://vercel.com/) is really cool! Love the
+simplicity of the service. You could compare it to
+[Netlify](https://www.netlify.com/).  I haven’t tried Netlify extensively, but
+from a couple of experimental deployments I still prefer Vercel. It is much more
+streamlined, but maybe this is bias in me. I really like Vercel’s Analytics,
+which give you a [Core Web Vitals report](https://web.dev/vitals/) in their
+admin console. Kind of cool, I’m not going to lie.
+
+This whole idea about frontend and backend merging into [SSR (server-side
+rendering)](https://www.debugbear.com/blog/server-side-rendering) looks so good
+on paper. It almost doesn’t come with any major flaws.
+
+But when it comes to the actual implementation, there is much to be desired.
+I’m going to lump [Next.js](https://nextjs.org/) and
+[Nuxt.js](https://nuxtjs.org/) together because they are essentially the same
+thing, just a different library.
+
+Now comes the reality. Mixing backend and frontend in this manner creates this
+weird mental model where you kind of rely on magical properties of these
+libraries. You relinquish control over to them for better developer experience.
+But is that really true? Initially, I was so stoked about it. However, the more
+I used them, the more I felt uncomfortable. I felt dirty, actually. Maybe this
+is because I come from old ways of doing things where you control every step of
+request, and allowing something to hijack it feels like blasphemy.
+
+More than that, some pretty significant technical issues arose from this. How do
+you do JWT token authentication? You put it in `api` folder and then do some
+fetching and storing into local state management. But doing this also requires
+some tinkering with await/async stuff on the React/Vue side of things. And then
+you need to write middleware for it. And the more I look at it, the more I see
+that this whole thing was not meant to be used like this, and it all feels and
+looks like a huge hack.
+
+The issue I have with this is that they over-promise and under-deliver. They
+want to be an all-in-one replacement for everything, and they don’t deliver on
+this promise. And how could they?! We have to be fair. It is an impossible task.
+
+They sell you [NoOps](https://www.geeksforgeeks.org/overview-of-noops/), but
+when you need to accomplish something a little bit more out of the scope of
+Hello World, you have to make hacky decisions to make it work. And having a
+deployment strategy that relies on many moving parts is never a good idea.
+Abstracting too much is usually a sign of bad architecture.
+
+Lately, this has become a huge trend that will for sure bite us in the future.
+And let’s not get it twisted. By doing this, PaaS providers like
+[AWS](https://aws.amazon.com/), [GCS](https://cloud.google.com/), etc. obscure
+their billing, and you end up paying more than you really should. And even if
+that is not an issue, it comes down to the principle of things. AWS is known for
+having multiple “currencies“ inside their projects like write operations, read
+operations, etc. which add up, and it creates this impossible to track billing
+scheme. It all behaves suspiciously like a pay-to-win game you could find on
+mobile phones that scams you out of your money.
+
+And as far as I am concerned, the most important thing was me not coding the
+functionalities for the game I want to make. I was battling libraries and cloud
+providers. How to deploy, what settings are relevant. Bad documentation or
+multiple versions of achieving the same thing. You are getting bombarded by all
+this information, and you don’t really have any control over it.
+Production-ready code becomes a joke, essentially. Especially if you tend to
+work on that project for a prolonged period of time.
+
+All of these options end up creating a fatigue. What to choose, what not to
+choose. Unnecessary worrying about if the stack will still be deemed worthy in
+six months. There is elegance in simplicity.
+
+> JavaScript UI frameworks and libraries work in cycles. Every six months or
+> so, a new one pops up, claiming that it has revolutionized UI development.
+> Thousands of developers adopt it into their new projects, blog posts are
+> written, Stack Overflow questions are asked and answered, and then a newer
+> (and even more revolutionary) framework pops up to usurp the throne.
+> — Ian Allen
+
+And this jab at these libraries and cloud providers is not done out of malice.
+It is a real concern that I have about them. In my life, I have seen
+technologies come and go, but the basics always stick around. So surrendering
+all the power you have to a library or a cloud provider is in my opinion a
+stupid move.
+
+## Tailwind CSS still rocks!
+
+You know, many people say negative things about Tailwind. And after a lot of
+deliberation, I came to the conclusion that Tailwind is good for two types of
+developers. Tailwind is good for a complete noob or a senior developer. A
+complete noob doesn’t really care about inner workings of CSS, and a senior
+developer also doesn’t care about CSS. Well, at least, not anymore. And
+developers in between usually have the biggest issues with it. Not always of
+course, but in a lot of cases.
+
+I like the creature comforts of Tailwind. Being utility first would make me
+argue that it is actually more similar to [Sass](https://sass-lang.com/) or
+[Less](https://lesscss.org/) than something like Bootstrap. Not technically, but
+ideologically. After I started using it, I never looked back. I use it every
+time I need to do something web related.
+
+Writing CSS for general things feels like going several steps back. Instead of
+focusing on what you are actually trying to achieve, you focus on notations like
+[BEM](https://en.bem.info/methodology/css/), code structuring, optimizing HTML
+size. Just doing things that make 0.1% difference. You know that saying: Early
+optimization is the root of all evil. Exactly that.
+
+I am also not saying that Tailwind is the cure for everything. Sometimes custom
+CSS is necessary. But from what I found out in using it for almost two years in
+a production environment (on a site getting quite a lot of traffic and
+constantly being changed), I can say without any reservations that Tailwind
+saved our asses countless times. We would be rewriting CSS all the time without
+it. And I don’t really think writing CSS is the best way to spend my time.
+
+I have also noticed that people who criticize Tailwind the most never actually
+used it in a real project that has a long lifetime with plenty of changes that
+will happen in the future.
+
+But you know, whatever floats your boat!
+
+## Code maintainability
+
+Somehow, people also stopped talking about maintenance. If you constantly try to
+catch the latest and greatest train, you are by that logic always trying new
+things. Which is a good thing if you want to learn about technologies and try
+them. But for the production environment, you have to have a stable stack that
+doesn’t change every 6 months.
+
+You can lock dependencies for sure. Nevertheless, the hype train moves along
+anyway. And the mindset this breeds goes against locking the code. This
+bleeding-edge rolling release cycle is not helping. That is why enterprise
+solutions usually look down on these popular stacks and only do bare minimum to
+appear hip and cool.
+
+With that said, I still think that progress is good, but should be taken with a
+grain of salt. If your project is something that should be built once and then
+rarely updated, going with the latest stack is a possible way to go. But, if you
+are working on a project that lasts for years, you should probably approach it
+with some level of caution. Web development is often times too volatile.
+
+## Web development has a marketing issue
+
+I noticed that almost every project now has this marketing spin put on it.
+Everything is blazingly fast now. I get it, they are competing for your
+attention, but what happened to just being truthful and not inflating reality.
+
+And in order to appeal to mass market, they leave things out of their marketing
+materials. These open-source projects are now behaving more and more like
+companies do. Which is a scary thought on its self.
+
+And we are also seeing a rise in a concept of building a company in the open,
+which is a good thing, don't get me wrong. But when it is using open-source to
+lure people and then lock them in their ecosystem, there is where I have issues
+with it.
+
+This might be because I have been using GNU/Linux for 20 years now and have been
+so beholden for my success to open-source that I see issues when open-source is
+being used to trick people into a false sense of security that these projects
+are built in the spirit of open-source. Because there is a difference. They are
+NOT! They have a really specific goal in mind. And the open-source is being used
+as a delivery system. Which is in my opinion disgusting!
+
+## Conclusion
+
+I will end my post with this. Web development is running now in circles. People
+are discovering [RPC](https://www.tutorialspoint.com/remote-procedure-call-rpc)
+now and this is the now the next big thing. [GraphQL](https://graphql.org/) is
+so passé. And I am so tired of it all. Of blazingly fast libraries, of all these
+new technologies that are actually just a remake of old ones. Of just the
+general spirit of the web. I will just use what I already know. Which worked 10
+years ago and will work 10 years after this. I will adopt a couple of little
+tools like Vite. But I will not waste my time on this anymore.
+
+It was a good exercise to get in touch with what’s new now. Nothing really
+changed that much. FOMO is now cured! Now I have to get my ass back to actually
+code and make the project that I wanted to make in the first place.
diff --git a/_posts/posts/2022-10-16-that-sound-that-machine-makes-when-struggling.md b/_posts/posts/2022-10-16-that-sound-that-machine-makes-when-struggling.md
new file mode 100644
index 0000000..7b019e9
--- /dev/null
+++ b/_posts/posts/2022-10-16-that-sound-that-machine-makes-when-struggling.md
@@ -0,0 +1,67 @@
+---
+title: Microsoundtrack — That sound that machine makes when struggling
+permalink: /that-sound-that-machine-makes-when-struggling.html
+date: 2022-10-16T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+A couple of months ago, I got an idea about micro soundtracks. In this concept,
+you are the observer, director, and audience in this tiny movies.
+
+What you do is to attempt to imagine what would be happening around you based on
+a title of the song and let the song help you fill the void in your story.
+
+I made these songs is Logic Pro X. Every year or so I do this kind of thing and
+make a couple of songs similar to this. But this is the first time I am posting
+about it.
+
+You can listen to the whole set on
+[Youtube](https://www.youtube.com/watch?v=_5oXBhSmF3c) or scroll down the page
+and there are embedded players for each song.
+
+## A bunch of inter-dimensional people with loud clocks
+
+A group of inter-dimensional people are going up and down the elevator with you
+while having loud clocks around their necks. Each clock ticks on a different
+frequency. A lot of other sounds are getting drawn into your dimension,
+resulting in a strange merging of dimensions.
+
+<iframe style="border: 0; width: 100%; height: 42px;" src="https://bandcamp.com/EmbeddedPlayer/album=3913808801/size=small/bgcol=ffffff/linkcol=0687f5/track=1349272965/transparent=true/" seamless title="Bandcamp"><a href="https://mitjafelicijan.bandcamp.com/album/that-sound-that-machine-makes-when-struggling">That sound that machine makes when struggling by Mitja Felicijan</a></iframe>
+
+## Two black holes conversing about the weather
+
+You are a traveler in a spaceship flying very close to two colliding black holes
+having a discussion about the weather while tearing each other apart. During all
+this your ship is getting pulled into the event horizon of both black holes,
+putting a lot of strain on your spaceship.
+
+<iframe style="border: 0; width: 100%; height: 42px;" src="https://bandcamp.com/EmbeddedPlayer/album=3913808801/size=small/bgcol=ffffff/linkcol=0687f5/track=1756714200/transparent=true/" seamless title="Bandcamp"><a href="https://mitjafelicijan.bandcamp.com/album/that-sound-that-machine-makes-when-struggling">That sound that machine makes when struggling by Mitja Felicijan</a></iframe>
+
+## A planet where every organism is a plant
+
+You land on a planet where every living organism is a plant and among those
+plants some of them are highly intelligent, and you were asked to make first
+contact with the native species. Your visit takes place in a giant cave where
+you are meeting these plants, and they are talking to you.
+
+<iframe style="border: 0; width: 100%; height: 42px;" src="https://bandcamp.com/EmbeddedPlayer/album=3913808801/size=small/bgcol=ffffff/linkcol=0687f5/track=3710973979/transparent=true/" seamless title="Bandcamp"><a href="https://mitjafelicijan.bandcamp.com/album/that-sound-that-machine-makes-when-struggling">That sound that machine makes when struggling by Mitja Felicijan</a></iframe>
+
+## Bio implants having a fit and reprogramming your brain
+
+In a distant future where everybody has bio implants, you have just received
+your first one, which happens to be a brain implant. Something goes wrong, and
+your implant is starting to misbehave, and you are experiencing brain
+malfunctions. You are on the streets at night a couple of hours after your
+procedure. You can feel your sanity breaking down.
+
+<iframe style="border: 0; width: 100%; height: 42px;" src="https://bandcamp.com/EmbeddedPlayer/album=3913808801/size=small/bgcol=ffffff/linkcol=0687f5/track=1157430581/transparent=true/" seamless title="Bandcamp"><a href="https://mitjafelicijan.bandcamp.com/album/that-sound-that-machine-makes-when-struggling">That sound that machine makes when struggling by Mitja Felicijan</a></iframe>
+
+## Cow animation
+
+I also made this little cow animation. Go into full screen to see the effects in
+more details.
+
+<video src="/assets/posts/microsoundtrack/cow.m4v" controls loop></video>
+
diff --git a/_posts/posts/2023-01-26-trying-to-build-a-new-kind-of-terminal-emulator.md b/_posts/posts/2023-01-26-trying-to-build-a-new-kind-of-terminal-emulator.md
new file mode 100644
index 0000000..ced58bb
--- /dev/null
+++ b/_posts/posts/2023-01-26-trying-to-build-a-new-kind-of-terminal-emulator.md
@@ -0,0 +1,254 @@
+---
+title: Trying to build a New kind of terminal emulator for the modern age
+permalink: /trying-to-build-a-new-kind-of-terminal-emulator.html
+date: 2023-01-26T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+Over the past few weeks, I have been really thinking about terminal emulators,
+how we interact with computers, the separation of text-based programs and GUI
+ones. To be perfectly honest, I got pissed off one evening when I was cleaning
+up files on my computer. Normally, I go into console and do `ncdu` and check
+where the junk is. Then I start deleting stuff. Without any discrimination,
+usually. But when it comes to screenshots, I have learned that it's good to keep
+them somewhere near if I need to refer to something that I was doing. I am an
+avid screenshot taker. So at that point I checked Pictures folder and also did a
+basic search `find . -type f -name "*.jpg"` for all the JPEG files in my home
+directory and immediately got pissed off. Why can’t I see thumbnails in my
+terminal? I know why, but why in the year of 2022 this is still a problem. I am
+used to traversing my disk via terminal. I am faster, and I am more comfortable
+this way. But when it comes to visualization, I then need to revert to GUI
+applications and again find the same file to see it. I know that programs like
+`feh` and `sxiv` are available, but I would just like to see the preview. Like
+[Jupyter notebook](https://jupyter.org/) or something similar.  Just having it
+inline. Part of a result.
+
+It also didn’t help that I was spending some time with the [Plan
+9](https://plan9.io/plan9/) Operating system. More specifically
+[9FRONT](http://9front.org/). The way that [ACME editor](http://acme.cat-v.org/)
+handles text editing is just wonderful. Different and fresh somehow, even though
+it’s super old.
+
+So, I went on a lookout for an interesting way of visualizing results of some
+query. I found these applications to be outstanding examples of how not to be a
+captive of a predetermined way of doing things.
+
+- [Wolfram Mathematica](https://www.wolfram.com/mathematica/)
+- [Jupyter notebooks](https://jupyter.org/)
+- [Plan 9 / 9FRONT](http://www.9front.org)
+- [Temple OS](https://templeos.org/)
+- [Emacs](https://www.gnu.org/software/emacs/)
+
+My idea is not as out there as ACME is, but it is a spin on the terminal
+emulators. I like the modes that Vi/Vim provides you with. I like the way the
+Emacs does its own `M-x` `M-c`.  Furthermore, I really like how Mathematica and
+Jupyter present the data in a free flowing form. And I love how Temple OS is
+basically a C interpreter on some level.
+
+> **Note:** This is part 1 of the journey. Nowhere finished yet. I am just 
+> tinkering with this at the moment. This whole thing can easily spectacularly 
+> fail.
+
+So I started. I knew that I wanted to have the couple of modes, but I didn’t
+like the repetition of keystrokes, so the only option was to have some sort of
+toggle and indicate to the user that they are in a special mode. Like Vi does
+for Normal and Visual mode.
+
+These modes would for the first version be:
+
+- *Preview mode* (toggle with Ctrl + P)
+    - When this mode would be enabled, the `ls` command would try to find images
+    from the results and display thumbnails from them in the terminal itself.
+    No ASCII art. Proper images. In a grid!
+- *Detach mode* (toggle with Ctrl + D)
+    - When this mode would be enabled, every command would open a new window 
+    and execute that command in it. This would be useful for starting `htop` 
+    in a separate window.
+
+The reason for having these modes togglable is to not ask for previews every
+time. You enable a mode and until you disable it, it behaves that way.  Purely
+out of ergonomic reasons.
+
+I would like to treat every terminal I open as a session mentally. When I start
+using the terminal, I start digging deeper into the issue I am trying to
+resolve.  And while I am doing this, I would like to open detached windows
+etc. A lot of these things can be done easily with something like
+[i3](https://i3wm.org/), but also that pull you out of the context of what you
+were doing. I would like to orchestrate everything from one single point.
+
+In planning for this project, I knew that I would need to use a language like C
+and a library such as [SDL2](https://www.libsdl.org/) in order to achieve the
+desired results. I had considered other options, but ultimately determined that
+[SDL2](https://www.libsdl.org/) was the best fit based on its capabilities and
+reputation in the programming community.
+
+At first, I thought the idea of a hardware accelerated terminal was a bit of a
+joke. It seemed like such a niche and unnecessary feature, especially given the
+fact that terminal emulators have been around for decades and have always relied
+on software rendering. But to be fair, [Alacritty](https://alacritty.org/) is
+doing the same thing. Well, they are doing a remarkable job at it.
+
+So, I embarked on a journey. Everything has to start somewhere. For me, it
+started with creating a window! It has to start somewhere. 🙂
+
+```c
+// Oh, Hi Mark!
+// Create the window, obviously.
+SDL_Window *window = SDL_CreateWindow(
+  WINDOW_TITLE, SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
+  WINDOW_WIDTH, WINDOW_HEIGHT,
+  SDL_WINDOW_RESIZABLE | SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN);
+```
+
+I continued like this to get some text displayed on the screen.
+
+I noted that
+[`TTF_RenderText_Solid`](https://wiki.libsdl.org/SDL_ttf/TTF_RenderText_Solid)
+rendered text really poorly. There were no antialiasing at all. In my wisdom, I
+never checked the documentation. Well, that was a fail. To uneducated like me:
+`TTF_RenderText_Solid` renders Latin1 text at fast quality to a new 8-bit
+surface. So, that's why the texts looked like shit. No wonder.
+
+Remarks on `TTF_RenderText_Solid`: This function will allocate a new 8-bit,
+palettized surface. The surface's 0 pixel will be the colorkey, giving a
+transparent background. The 1 pixel will be set to the text color.
+
+After I replaced it with
+[`TTF_RenderText_LCD`](https://wiki.libsdl.org/SDL_ttf/TTF_RenderText_LCD) which
+renders Latin1 text at LCD subpixel quality to a new ARGB surface, the text
+started looking good. Really make sure you read the documentation. It’s actually
+good. As a side note, you can find all the documentation regarding [SDL2 on
+their Wiki](https://wiki.libsdl.org/).
+
+After that was done, I started working on displaying other things like `Preview`
+and `Detach` modes. This wasn’t really that hard. In SDL2 you can check all the
+available events with `while (SDL_PollEvent(&event) > 0)` and have a bunch of
+switch statements to determine which key is currently being pressed. More about
+keys, [SDLKey](https://documentation.help/SDL/sdlkey.html) and mroe about
+pooling the events on
+[SDL_PollEvent](https://documentation.help/SDL/sdlpollevent.html).
+
+```c
+while (SDL_PollEvent(&event) > 0)
+{
+  switch (event.type)
+  {
+  case SDL_QUIT:
+    running = false;
+    break;
+
+  case SDL_TEXTINPUT:
+    if (!meta_key_pressed)
+    {
+      strncat(input_prompt_text, event.text.text, 1);
+      update_input_prompt = true;
+    }
+    break;
+        }
+}
+```
+
+After that was somewhat working correctly, I started creating a struct that
+would hold all the commands and results and I call them Cells. Yes, I stole that
+naming idea from Jupyter.
+
+```c
+typedef struct
+{
+  char *command;
+  char *result;
+  SDL_Surface *surface;
+  SDL_Texture *texture;
+  SDL_Rect rect;
+} Cell;
+```
+
+I am at a place now where I am starting to implement scrolling. This will for
+sure be fun to code. Memory management in C is super easy. 😂
+
+I have also added a simple [INI file like
+configuration](https://en.wikipedia.org/wiki/INI_file) support. It is done in an
+[STB style of
+header](https://github.com/nothings/stb/blob/master/docs/stb_howto.txt) and maps
+to specific options supported by the terminal. It is not universal, and the code
+below demonstrates how I will use it in the future.
+
+```c
+#ifndef CONFIG_H
+#define CONFIG_H
+
+/*
+# This is a comment
+
+# This is the first configuration option
+dettach=value11111
+
+# This is the second configuration option
+preview=value22222
+
+# This is the third configuration option
+debug=value33333
+*/
+
+// Define a struct to hold the configuration options
+typedef struct
+{
+    char dettach[256];
+    char preview[256];
+    char debug[256];
+} Config;
+
+// Read the configuration file and return the options as a struct
+extern Config read_config_file(const char *filename)
+{
+  // Create a struct to hold the configuration options
+  Config config = {0};
+
+  // Open the configuration file
+  FILE *file = fopen(filename, "r");
+
+  // Read each line from the file
+  char line[256];
+  while (fgets(line, sizeof(line), file))
+  {
+    // Check if this line is a comment or empty
+    if (line[0] == '#' || line[0] == '\n')
+      continue;
+
+    // Parse the line to get the option and value
+    char option[128], value[128];
+    if (sscanf(line, "%[^=]=%s", option, value) != 2)
+      continue;
+
+    // Set the value of the appropriate option in the config struct
+    if (strcmp(option, "dettach") == 0)
+    {
+      strncpy(config.option1, value, sizeof(config.option1));
+    }
+    else if (strcmp(option, "preview") == 0)
+    {
+      strncpy(config.option2, value, sizeof(config.option2));
+    }
+    else if (strcmp(option, "debug") == 0)
+    {
+      strncpy(config.option3, value, sizeof(config.option3));
+    }
+  }
+
+  // Close the configuration file
+  fclose(file);
+
+  // Return the configuration options
+  return config;
+}
+
+#endif
+```
+
+This is as far as I managed to get for now. I have a daily job and this
+prohibits me to work on these things full time. But I should probably get back
+and finish this. At least have a simple version working out, so I can start
+testing it on my machines. Fingers crossed. 🕵️‍♂️
+
diff --git a/_posts/posts/2023-05-16-rekindling-my-love-for-programming.md b/_posts/posts/2023-05-16-rekindling-my-love-for-programming.md
new file mode 100644
index 0000000..dc5344f
--- /dev/null
+++ b/_posts/posts/2023-05-16-rekindling-my-love-for-programming.md
@@ -0,0 +1,75 @@
+---
+title: Rekindling my love for programming and enjoying the act of creating
+permalink: /rekindling-my-love-for-programming.html
+date: 2023-05-16T12:00:00+02:00
+layout: post
+type: post
+draft: false
+---
+
+Programming can be a challenging and rewarding experience, but sometimes it's
+easy to feel burnt out or disinterested. I have lost the passion for coding over
+the past couple of months and it looked like I will never enjoy the coding as
+much as I did.
+
+I was feeling burnt out with programming. I thought taking a break from it and
+focusing on other activities that I enjoy might be helpful. This way, I could
+come back to programming with a fresh perspective and renewed energy.  I also
+thought about learning a new programming language or technology to keep things
+interesting and challenging.
+
+However, what I didn't realize was that learning a new language or technology
+wasn't going to solve the underlying issue. I needed to take a step back and
+re-evaluate why I had lost my passion for programming in the first place.  This
+involved taking a deep look into what I was doing that resulted in this rut.
+
+Sometimes, it's easy to get caught up in the hype of new technologies or
+languages, and we can feel like we're missing out if we're not constantly
+learning and experimenting. However, it's important to remember that the latest
+and greatest isn't always the best fit for our projects or our
+interests. Instead of constantly chasing the next big thing, it can be helpful
+to focus on what truly interests us and what we're passionate about. This can
+help us stay motivated and engaged with our work, rather than feeling like we're
+just going through the motions.
+
+I expressed that I had lost my passion for coding over the past couple of
+months, and I realized that the reason behind it was my tendency to spread
+myself too thin and not focus on completing interesting projects. In order to
+regain my passion for coding, I need to focus on projects that truly interest me
+and give me a sense of purpose and motivation.
+
+Recently, I have been playing World of Warcraft more frequently and have become
+interested in developing addons for the game.
+
+This quickly resulted in me creating three addons that improve the quality of
+life, and I subsequently developed a more useful add-on that encapsulates all
+the others I made.
+
+I found it interesting that this action sparked a new interest in me.
+Additionally, I discovered the Lua language, which reminded me that coding
+should be fun rather than just a struggle with a language. It should be pure,
+unadulterated fun.
+
+I wasn't fighting the syntax, nor was I focused on finding the most optimal
+solution. I simply created things without the pressure of making them the best
+they could possibly be.
+
+This made me realize that I actually adore simple languages that get out of the
+way and let you express what you want to do. It forced me to rethink a lot about
+what I use and what I actually enjoy.
+
+I have decided to stick to the basics. For a scripting language, I will use
+Lua. For networking, I will use Golang. And for any special needs, I will rely
+on C. I do not require Rust, Nim, or Zig. This selection is more than sufficient
+for my needs. I have to stay true to this simplicity. There is something to the
+Occam's Razor.
+
+I've been struggling with a lack of creativity lately, but now I'm experiencing
+a real change. I realized I needed to take a step back and stop actively trying
+to address the issue. I needed to stop worrying and overthinking it. I simply
+needed some time. Looking back, I don't think I've taken any significant time
+off in the last 10 years.
+
+Suddenly, I find myself with the energy and passion to complete multiple small
+projects. It doesn't feel like a chore at all. Who knew I needed WoW to
+kickstart everything. Inspiration really does come from the strangest places.
diff --git a/_posts/posts/2023-05-23-i-was-wrong-about-git-workflows.md b/_posts/posts/2023-05-23-i-was-wrong-about-git-workflows.md
new file mode 100644
index 0000000..57d887c
--- /dev/null
+++ b/_posts/posts/2023-05-23-i-was-wrong-about-git-workflows.md
@@ -0,0 +1,72 @@
+---
+title: I think I was completely wrong about Git workflows
+permalink: /i-was-wrong-about-git-workflows.html
+date: 2023-05-23T12:00:00+02:00
+layout: post
+type: post
+draft: false
+tags: []
+---
+
+I have been using some approximation of [Git
+Flow](https://jeffkreeftmeijer.com/git-flow/) for years now and never really
+questioned it to be honest. When I create a repo I create develop branch and set
+it as default one and then merge to master from there. Seems reasonable enough.
+
+One thing that I have learned is that long living branches are the devil.  They
+always end up making a huge mess when they need to be merged eventually into
+master. So by that reason, what is the develop branch if not the longest living
+feature branch. And from my personal experience there was never a situation
+where I wasn’t sweating bullets when I had to merge develop back to master.
+
+This realisation started to give me pause. So why the hell am I doing this, and
+is there a better way. Well the solution was always there. And it comes in a
+form of [git tags](https://git-scm.com/book/en/v2/Git-Basics-Tagging).
+
+So what are git tags? Git tags are references to specific points in a Git
+repository's history. They are used to mark important milestones, such as
+releases or significant commits, making it easier to identify and access
+specific versions of a project.
+
+Somehow we have all hijacked the meaning of the master branch that it has to be
+the most releasable version of code. And this is also where the confusing about
+versioning the software kicks in. Because master branch implicitly says that we
+are dealing with the rolling release type of a software. And by having a develop
+branch we are hacking around this confusion. With a separation of develop and
+master we lock functionalities into place and forcing a stable vs development
+version of the software.
+
+But if that is true and the long living branches are the devil then why have
+develop at all. I think that most of this comes to how continuous integration is
+being done. There usually is no granular access to tags and CD software deploys
+what is present on a specific branch, may that be master for production and
+develop for staging. This is a gross simplification and by having this in place
+we have completely removed tagging as a viable option to create a fix point in
+software cycle that says, this is the production ready code.
+
+One cool thing about tags are that you can checkout a specific tag. So they
+behave very similarly as branches in that regard. And you don’t have the
+overhead of having two mainstream branches.
+
+So what is the solution? One approach is to use development workflow, where all
+changes are made on the smaller branches and continuously merged into
+master. Where the software is ready to be pushed to production you tag the
+master branch. This approach eliminates the need for long-lived branches and
+simplifies the development process. It also encourages developers to make small,
+incremental changes that can be tested and deployed quickly. However, this
+approach may not be suitable for all projects or teams that heavily rely on
+automated deployment based on branch names only.
+
+This also requires that developers always keep production in mind. No more
+living on an island of the develop branch. All your actions and code need to be
+ready to meet production standards on a much smaller timescale.
+
+I think that we have complicated the workflow in an honest attempt to make
+things more streamlined but in the process of doing this, we have inadvertently
+made our lives much more complicated.
+
+In conclusion, it's important to re-evaluate our workflows from time to time to
+see if they still make sense and if there are better alternatives available.
+Long-living branches can be problematic, and using tags to mark important
+milestones can simplify the development process.
+
diff --git a/_posts/posts/2023-05-31-re-inventing-task-runner-that-i-actually-used-daily.md b/_posts/posts/2023-05-31-re-inventing-task-runner-that-i-actually-used-daily.md
new file mode 100644
index 0000000..c595905
--- /dev/null
+++ b/_posts/posts/2023-05-31-re-inventing-task-runner-that-i-actually-used-daily.md
@@ -0,0 +1,160 @@
+---
+title: "Re-Inventing Task Runner That I Actually Used Daily"
+permalink: /re-inventing-task-runner-that-i-actually-used-daily.html
+date: 2023-05-31T12:21:10+02:00
+layout: post
+type: post
+draft: false
+---
+
+Couple of months ago I had this brilliant idea of re-inventing the wheel by
+making an alternative for make. And so I went. Boldly into the battle. And to my
+big surprise my attempt resulted in not a completely useless piece of software.
+
+My initial requirements were quite simple but soon grow into something more
+ambitious. And looking back I should have stuck to the simple version. My
+laziness was on my side this time though. Because I haven’t implemented some of
+the features I now realise I really didn’t need them and they would bog the
+whole program and make it be something it was never meant to be.
+
+My basic requirements were following:
+
+- Syntax should be a tiny bit inspired by Rake and Rakefiles.
+- Should borrow the overall feel of a unit test experience.
+- Using something like Python would be a bit of an overkill.
+- The program must be statically compiled, so it can run on same architecture
+  without libc, musl dependencies or things like that.
+- Install ruby for rake is a bit overkill and can not be done with certain
+  really lightweight distributions like Alpine Linux. This tool would be usable
+  on such lightweight systems for remote debugging.
+- I want to use it for more than just compiling things. I want to use it as an
+  entry-point into a project, and I want this to help me indirectly document the
+  project as well.
+- It should be an abstraction over bash shell or the default system shell.
+    - Each task essentially becomes its own shell instance.
+- Must work on Linux and macOS systems.
+- By default, running `erd` list all the available tasks (when I use make, I
+  usually put a disclaimer that you should check Makefile to see all available
+  target).
+- Should support passing arguments when you run it from a shell.
+- Normal variable as the same as environmental variables. There is no
+  distinction. Every variable is also essentially an environment variable and
+  can be used by other programs.
+- State between tasks is not shared, and this makes this “pure” shell instances.
+- Should be single-threaded for the start and later expanded with `@spawn`
+  command.
+- Variables behave like macros and are preprocessed before evaluation.
+- Should support something like `assure` that would check if programs like C
+  compiler or Python (whatever the project requires) are installed on a machine.
+
+Quite a reasonable list of requirements. I do this things already in my
+Makefiles or/and Bash scripts. But I would like to avoid repeating myself every
+time I start working on something new.
+
+So I started with the following syntax.
+
+```ruby
+@env on
+
+# Override the default shell.
+@shell /bin/bash
+
+# Assure that program is installed.
+@assure docker-compose pip python3
+
+# Load local dotenv files (these are then globally available).
+@dotenv .env
+@dotenv .env.sample
+@dotenv some_other_file
+
+# This are local variables but still accessible in tasks.
+@var HI = "hey"
+@var TOKEN = "sometoken"
+@var EMAIL = "m@m.com"
+@var PASSWORD = "pass"
+@var EDITOR = "vim"
+
+@task dev "Test chars .:'}{]!//" does
+  echo "..." $HI
+end
+
+@task clean "Cleans the obj files" does
+  rm .obj
+end
+
+@task greet "Greets the user" does
+  echo "Hi user $TOKEN or $WINDOWID $EMAIL"
+end
+
+@task stack "Starts Docker stack" does
+  docker-compose -f stack.yml up
+end
+
+@task todo "Shows all todos in source files and count them" does
+  grep -ir "TODO|FIXME" . | wc -l
+end
+
+@task test1 "For testing 1" does
+  unknown-command
+  echo "test1"
+  ls -lha
+end
+
+@task test2 "For testing 2" does
+  echo "test1"
+  ls -lha
+  docker-compose -f samples/stack.yml up
+end
+```
+
+One thing that I really like about Errand. Yes, this is what it is called. And
+it is available at https://git.mitjafelicijan.com/errand.git/about/. Moving
+on. One thing that I really like is that a task is a persistent shell. By that I
+mean, that the whole task, even if it contains multiple command in one shell.
+In make each line in a target is that and you need to combine lines or add `\`
+at the end of the line.
+
+```bash
+# How you do this things in make.
+target:
+        source .venv/bin/activate \
+        python script.py
+```
+
+This solves this problem. Consider each task and what is being executed in that
+task a shell that will only close when all the tasks are completed.
+
+By self-documenting I mean that if you are in a directory with `Errandfile` in,
+if you only type `erd` and press enter it should by default display all the
+possible targets. In make i was doing this by having a first target be something
+like `default` that echos the message “Check Makefile for all available target.”
+Because all of the tasks in Errand require a message I use that to display let’s
+call it table of contents.
+
+Because I don’t use any external dependencies this whole thing can be statically
+compiled. So that also checked one of the boxes.
+
+It works on Linux and on a Mac so that’s also a bonus. I don’t believe this
+would work on Windows machines because of the way that I use shell instances. By
+you could use something like Windows Subsystem for Linux and run it in
+there. That is a valid option.
+
+To finish this essay off, how was it to use it in “real life”. I have to be
+honest. Some of the missing features still bother me. `@dotenv` directive is
+still missing and I need to implement this ASAP.
+
+Another thing that needs to happen is support for streaming output. Currently
+commands like `docker-compose` that runs in foreground mode is not compatible
+with Errand. So commands that stream output are an issue.  I need to revisit how
+I initiate shell and how I read stdout and stderr.  But that shouldn’t be a
+problem.
+
+I have been very satisfied with this thing. I am pleasantly surprised by how
+useful it is. I really wanted to test this in the wild before I commit to it. I
+have more abandoned project than Google and it’s bringing a massive shame to my
+family at this point. So I wanted to be sure that this is even useful. And it
+actually is. Quite surprised at myself.
+
+I really need to package this now and write proper docs. And maybe rewrite
+tokeniser. Its atrocious right now. Site to behold! But that is an issue for
+another time.
diff --git a/_posts/posts/2023-07-01-bringing-all-of-my-projects-together-under-one-umbrella.md b/_posts/posts/2023-07-01-bringing-all-of-my-projects-together-under-one-umbrella.md
new file mode 100644
index 0000000..4bc45ce
--- /dev/null
+++ b/_posts/posts/2023-07-01-bringing-all-of-my-projects-together-under-one-umbrella.md
@@ -0,0 +1,282 @@
+---
+title: "Bringing all of my projects together under one umbrella"
+permalink: /bringing-all-of-my-projects-together-under-one-umbrella.html
+date: 2023-07-01T18:49:07+02:00
+layout: post
+type: post
+draft: false
+---
+
+## What is the issue anyway?
+
+Over the years, I have accumulated a bunch of virtual servers on my
+[DigitalOcean](https://www.digitalocean.com/) account for small experimental
+projects I dabble in. And this has resulted in quite a bill. I mean, I wouldn't
+care if these projects were actually being used. But there were just being there
+unused and wasting resources. Which makes this an unnecessary burden for me.
+
+Most of them are just small HTML pages that have an endpoint or two to read data
+from or to, and for that reason I wrote servers left and right. To be honest,
+all of those things could have been done with [CGI
+scripts](https://en.wikipedia.org/wiki/Common_Gateway_Interface) and that would
+have been more than enough.
+
+Recently, I decided to stop language hopping and focus on a simpler stack which
+includes C, Go and Lua. And I can accomplish all the things I am interested in.
+
+## Finding a web server replacement
+
+Usually I had [Nginx](https://nginx.org/en/) in front of these small web servers
+and I had to manage SSL certificates and all that jazz. I am bored with these
+things. I don't want to manage any of this bullshit anymore.
+
+So the logical move forward was to find a solid alternative for this. I have
+ended up on [Caddy server](https://caddyserver.com/). I've used it in the past
+but kind of forgotten about it. What I really like about it is an ease of use
+and a bunch of out of the box functionalities that come with it.
+
+These are the _pitch_ points from their website:
+
+- **Secure by Default**: Caddy is the only web server that uses HTTPS by
+  default. A hardened TLS stack with modern protocols preserves privacy and
+  exposes MITM attacks.
+- **Config API**: As its primary mode of configuration, Caddy's REST API makes
+  it easy to automate and integrate with your apps.
+- **No Dependencies**: Because Caddy is written in Go, its binaries are entirely
+  self-contained and run on every platform, including containers without libc.
+- **Modular Stack**: Take back control over your compute edge. Caddy can be
+  extended with everything you need using plugins.
+
+I had just a few requirements:
+
+- Automatic SSL
+- Static file server
+- Basic authentication
+- CGI script support
+
+And the vanilla version does all of it, but CGI scripts. But that can easily be
+fixed with their modular approach. You can do this on their website and build a
+custom version of the server, or do it with Docker.
+
+This is a `Dockerfile` I used to build a custom server.
+
+```Dockerfile
+FROM caddy:builder AS builder
+
+RUN xcaddy build \
+  --with github.com/aksdb/caddy-cgi
+
+FROM caddy:latest
+RUN apk add --no-cache nano
+
+COPY --from=builder /usr/bin/caddy /usr/bin/caddy
+```
+
+## Getting rid of all the unnecessary virtual machines
+
+The next step was to get a handle on the number of virtual servers I have all
+over the place.
+
+I decided to move all the projects and services into two main VMs:
+
+- personal server (still Nginx)
+  - git server
+  - static file server
+  - personal blog
+- projects server (Caddy server)
+  - personal experiments
+  - other projects
+
+I will focus on projects' server in this post since it's more interesting.
+
+## Testing CGI scripts
+
+The first thing I tested was how CGI scripts work under Caddy. This is
+particularly import to me because almost all of my experiments and mini projects
+need this to work.
+
+To configure Caddy server, you must provide the server with a configuration
+file. By default, it's called `Caaddyfile`.
+
+```caddyfile
+{
+  order cgi before respond
+}
+
+examples.mitjafelicijan.com {
+  cgi /bash-test /opt/projects/examples/bash-test.sh
+  cgi /tcl-test /opt/projects/examples/tcl-test.tcl
+  cgi /lua-test /opt/projects/examples/lua-test.lua
+  cgi /python-test /opt/projects/examples/python-test.py
+
+  root * /opt/projects/examples
+  file_server
+}
+```
+
+- The order is very important. Make sure that `order cgi before respond` is at
+  the top of the configuration file.
+- Also, when you run with Caddy v2, make sure you provide `adapter` argument
+  like this `/usr/bin/caddy run --watch --environ --config /etc/caddy/Caddyfile
+  --adapter caddyfile`. Otherwise, Caddy will try to use a different format for
+  config file.
+
+I did a small batch of tests with [Bash](https://www.gnu.org/software/bash/),
+[Tcl](https://www.tcl-lang.org/), [Lua](https://www.lua.org/) and
+[Python](https://www.python.org/). Here is a cheat sheet if you need it.
+
+Let's get Bash out of the way first.
+
+```bash
+#!/usr/bin/bash
+
+printf "Content-type: text/plain\n\n"
+
+printf "Hello from Bash\n\n"
+printf "PATH_INFO     [%s]\n" $PATH_INFO
+printf "QUERY_STRING  [%s]\n" $QUERY_STRING
+printf "\n"
+
+for i in {0..9..1}; do
+  printf "> %s\n" $i
+done
+
+exit 0
+```
+
+This one is for Tcl script.
+
+```tcl
+#!/usr/bin/tclsh
+
+puts "Content-type: text/plain\n"
+
+puts "Hello from Tcl\n"
+puts "PATH_INFO     \[$env(PATH_INFO)\]"
+puts "QUERY_STRING  \[$env(QUERY_STRING)\]"
+puts ""
+
+for {set i 0} {$i < 10} {incr i} {
+  puts "> $i"
+}
+```
+
+And for all you Python enjoyers.
+
+```python
+#!/usr/bin/python3
+
+import os
+
+print("Content-type: text/plain\n")
+
+print("Hello from Python\n")
+print("PATH_INFO     [{}]".format(os.environ['PATH_INFO']))
+print("QUERY_STRING  [{}]".format(os.environ['QUERY_STRING']))
+print("")
+
+for i in range(10):
+  print("> {}".format(i))
+```
+
+And for the final example, Lua.
+
+```lua
+#!/usr/bin/lua
+
+print("Content-type: text/plain\n")
+
+print("Hello from Lua\n")
+print(string.format("PATH_INFO     [%s]", os.getenv("PATH_INFO")))
+print(string.format("QUERY_STRING  [%s]", os.getenv("QUERY_STRING")))
+print()
+
+for i = 0, 9 do
+  print(string.format("> %d", i))
+end
+```
+
+## Basic authentication
+
+One thing was also to have an option for some sort of authentication, and
+something like [Basic access
+authentication](https://en.wikipedia.org/wiki/Basic_access_authentication) would
+be more than enough.
+
+Thankfully, Caddy supports this out of the box already. Below is an updated
+example.
+
+```Caddyfile
+{
+    order cgi before respond
+}
+
+examples.mitjafelicijan.com {
+  cgi /bash-test /opt/projects/examples/bash-test.sh
+  cgi /tcl-test /opt/projects/examples/tcl-test.tcl
+  cgi /lua-test /opt/projects/examples/lua-test.lua
+  cgi /python-test /opt/projects/examples/python-test.py
+
+  root * /opt/projects/examples
+  file_server
+
+  basicauth * {
+    bob $2a$14$/wCgaf9oMnmQa20txB76u.nI1AldGMBT/1J7fXCfgOiRShwz/JOkK
+  }
+}
+```
+
+`basicauth *` matches everything under this domain/sub-domain and protects it
+with Basic Authentication.
+
+- `bob` is the username
+- `hash` is the password
+
+To generate these passwords, execute `caddy hash-password` and this will prompt
+you to insert a password twice and spit out a hashed password that you can put
+in your configuration file.
+
+Restart the server and you are ready to go.
+
+## Making Caddy a service with systemd
+
+After the tests were successful, I copied `caddy` to `/usr/bin/caddy` and copied
+`Caddyfile` to `/etc/caddy/Caddyfile`.
+
+Now off to the systemd. Each systemd service requires you to create a service
+file.
+
+- I created a `/etc/systemd/system/caddy.service` and put the following content
+  in the file.
+
+```systemd
+[Unit]
+Description=Caddy
+Documentation=https://caddyserver.com/docs/
+After=network.target network-online.target
+Requires=network-online.target
+
+[Service]
+Type=notify
+User=root
+Group=root
+ExecStart=/usr/bin/caddy run --environ --config /etc/caddy/Caddyfile --adapter caddyfile
+ExecReload=/usr/bin/caddy reload --config /etc/caddy/Caddyfile --force --adapter caddyfile
+TimeoutStopSec=5s
+LimitNOFILE=1048576
+LimitNPROC=512
+PrivateTmp=true
+ProtectSystem=full
+AmbientCapabilities=CAP_NET_ADMIN CAP_NET_BIND_SERVICE
+
+[Install]
+WantedBy=multi-user.target
+```
+
+- You might need to reload systemd with `systemctl daemon-reload`.
+- Then I enabled the service with `systemctl enable caddy.service`.
+- And then I started the service with `systemctl start caddy.service`.
+
+This was about all that I needed to do to get it running. Now I can easily add
+new subdomains and domains to the main configuration file and be done with
+it. No manual Let's Encrypt shenanigans needed.
diff --git a/_posts/posts/2023-07-08-who-knows-what-the-world-will-look-like-tomorrow.md b/_posts/posts/2023-07-08-who-knows-what-the-world-will-look-like-tomorrow.md
new file mode 100644
index 0000000..c7d52d5
--- /dev/null
+++ b/_posts/posts/2023-07-08-who-knows-what-the-world-will-look-like-tomorrow.md
@@ -0,0 +1,101 @@
+---
+title: "Who knows what the world will look like tomorrow"
+permalink: /who-knows-what-the-world-will-look-like-tomorrow.html
+date: 2023-07-08T18:49:07+02:00
+layout: post
+type: post
+draft: false
+---
+
+This site has gone through a lot of changes over the years. From being written
+in Flask and Bottle to moving on to static site generators. I have used and
+tested probably 10s of them my now. From homebrew solutions to the biggest and
+the baddest. From Bash scripts to Node.js disasters. I've seen some things, no
+doubt. Not all bad.
+
+I have been closely observing the web and where the trends are going, and I
+don't like what I see. Instead of internet being this weird place where
+experimentation is happening, it all became stale and formulized. Boring,
+actually. Really boring. And sad. Where is that old, revolutionary FU spirit I
+remember? It's still there, I know. But it's being drowned by the voices of
+mediocrity and formulaic boredom.
+
+It almost feels like that the internet stopped for 10 years and only now
+something has started happening. With all the insanity around the world. People
+hating people without actual reasons, just because it's fashionable to hate and
+crowd is saying so. Sad state of affairs.
+
+All this is contributing to this overall negativity masked as apathy. Everybody
+walking in lockstep. Instead of being creative and bold, we are just
+re-inventing the world and making the same mistakes. Maybe, just maybe, some
+things are good enough and there is no need to try to be too smart for our own
+good. After N-attempts, maybe something should click inside our heads to maybe
+say: "This thing, opinion, etc. is actually really good, and even after several
+attempts it still holds."
+
+The older I get, the more careful I am of my own thoughts and why I think the
+way I think. More and more, I try to understand people with opposite
+opinions. Far from perfect, but closer to bearable. And then I see people
+hearing or reading a thing on internet and let's fucking goooooo! Strong
+opinions are a sign of a weak and uneducated mind. I am more and more sure of
+this.
+
+It's gotten to a point where you can with great certainty deduce a person's
+personality based on one or two opinions. How boring have we become. No wonder
+people can't talk to each other. These would be very quick conversations anyway.
+
+I just got remembered of a song, ["Hi
+Ren"](https://www.youtube.com/watch?v=s_nc1IVoMxc). The ending talks about being
+stiff and not being able to dance. Such an amazing metaphor. And we as people
+have gone so far, we can't even walk or even crawl normally anymore. We have
+forgotten that the most beautiful things in life have a great deal of
+uncertainty about them. We want instant gratification. Not only that, but we
+want absolute obedience. Complete control over others, because we have zero
+control of ourselves. And all the lies we could tell ourselves will not help us
+out of this situation.
+
+It is funny how I catch myself from time to time being a complete idiot. It's
+like having an outer body experience. I can see myself being an idiot, and
+cannot stop myself. It serves as a learning lesson to stop before speaking. To
+think before saying. And to crawl before walking.
+
+So there is still time. We can dance once more. All we need to do is stop for a
+second. Me and you. Us two is a start. Let's not try to change the world, but
+rather nudge ourselves just a tiny bit. And if we only did that?! Just
+imagine. Each of us nudged ourselves a small, tiny bit, the world would heal. If
+we would just put down the phones and ignored Internet for a day or two. Put
+visiting websites that feed on us on hold. Listened to just one sentence and try
+to understand it from a person who we completely disagree with. I truly believe
+that this is possible.
+
+Life is about suffering and joy. And instead of wishing suffering on others and
+excepting joy for yourselves, we should for a brief moment want suffering for
+ourselves and wish joy on others. Wouldn't that be an amazing sight to see?
+
+I caught myself hating on Rust. And I deeply thought about it afterward. Why did
+I do it? It is obviously not for me. So why the hell was I being so negative
+towards it? I think that I know the answer. I was negative because that is
+easy. Because it's much easier to hate on things than to say to yourself: "Well,
+you know what? This is not for me. I will focus on creation and not
+destruction. This is who I want to be. This is what fills me with joy and
+purpose." Where joy is keeping me happy and purpose scares the shit out of me
+and keeps me honest. This is who I want to be. Admit to myself when I am wrong
+and accept the faults that I have without reservation and with courage march on.
+
+I just realized that this blog post is a sort of therapy for me. It's
+cathartic. Going thought the history of this site and remembering all the
+decisions and annoyances that came with it. When I was cursing at the tools. And
+time moved on, and the site is still here. It serves as a reminder that
+perseverance wins at the end. If we just let things go.
+
+This came with a decision that simplifying life and removing all the unnecessary
+negativity is key. Rather than worrying about what the internet is saying, what
+the world is trying to take from you, you are the only one who can say no. And
+create instead of destroy.
+
+I don't have an ending for this post, so I will say this. We live in the most
+amazing times in the recorded history, and we should be internally grateful for
+it. Create and study, this should be my mantra. Just create and let the world
+happen. And when you feel yourself to be too certain, stop and check how deep in the
+shit you are already. Strong opinions are a sign of a weak and uneducated
+mind. Hate and disdain is for the weak.
diff --git a/_posts/posts/2023-11-05-elitist-attitudes-are-sapping-the-fun-from-programming.md b/_posts/posts/2023-11-05-elitist-attitudes-are-sapping-the-fun-from-programming.md
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+---
+title: "Elitist attitudes are sapping all the fun from programming"
+permalink: /elitist-attitudes-are-sapping-all-the-fun-from-programming.html
+date: 2023-11-05T09:04:28+02:00
+layout: post
+type: post
+draft: false
+---
+
+It's always been like that. Maybe it was even worse before, and I am remembering
+it with rose-tinted glasses. But from the best that I can remember, it had at
+least some roots in reality. If something was objectively bad, you could point
+to it. But what I have started noticing recently is that objectivity is not the
+only condition to bash on something. More and more, you can use subjective
+opinion to say horrible things about technology, language or just a specific
+manufacturer.
+
+And all this has achieved is that I don't really listen to anybody anymore. I
+don't care what you think about X or Y. I don't care if you like this language
+or that one. I don't care if you prefer Dell to ThinkPad over Macbook. Who gives
+a fuck, anyway? If you can do your job on it, why even care about this stuff at
+all. And if you can't, buy a different machine.
+
+It's like the politics weren't enough. Now the same tribalism is here as well. C
+developers hating on Rust. JavaScript developers laughing at jQuery users. Rust
+developers laughing at everybody except Haskell users. And everybody laughing at
+JavaScript. It's like this never-ending dream, being stuck in high school. Us
+against your team. It's like we are all stuck being 16. Such a sad state of
+affair. And it's always been like this. But it's getting worse I think.
+
+Everybody trying to be elitist. Compensating lack of JavaScript features (like
+type system, for one) with coming up with this insane terminology to make
+JavaScript sound more sophisticated, as it is. Let's invent terminology to hide
+flaws and sound more educated and academic. And the same goes for C and all the
+other languages. All languages are shitty in some ways. For the love of God,
+why? Just let it be. For once, let things just be.
+
+And I, for one, just do not care anymore. Languages are tools and not your
+identity. If you need a programming language to fill a void in your life, I
+strongly suggest that you re-evaluate where you stand currently. Try something
+else. You are not a C developer, or Go developer, or JavaScript developer. You
+are a problem solver. That's what you are. And be damn proud of it. You don't
+need a label to make that more true or more sophisticated.
+
+I use Linux and macOS. I have fun on both systems. In my personal experience,
+Macbooks are better laptops for what I need them to be. They are better fit for
+me. Portable machines with an amazing battery life. That's all that I need from
+a laptop. I don't need to come up with this insane hypothetical scenarios where
+it will fell short. Yes, it can't water the plants when I am sleeping. OMG, are
+we really going there. These insane hypotheticals. Who really cares? I don't! I
+use it, it does what I need it to do, and that is the end of the story. Not only
+that, but I don't push this down other people's throats. Like Tsodings often
+says: It is what it is, and it isn't what it isn't. Such wise words. On my main
+machine I have Linux and had it for more than 20 years and I love it. I LOVE
+it. I am used to it. And I've had some shitty experiences with it, but damn it,
+I love it. It does what it needs to do. It fits my needs. And if I needed
+Windows, I would find a way to love it too. Why not? There is enough love to go
+around where you are not being elitist and a shithead.
+
+Programming should be fun. Not going through a checklist before you even start,
+to see if you are using what is considered the “cool” thing. If you are doing
+this, you already failed in my opinion.
+
+Oh, you are not using this “insert here” algorithm? Such a pleb. Don't you know
+about O(N) complexity? OMG, such a noob. He doesn't know. Uneducated pleb. 2017
+called, and they want their stack back.
+
+Yes, there is a place for all of those things. But not everything needs to be
+perfect. There is an awesome quote in Uncharted: Sic Parvis Magna. “greatness,
+from small beginnings.”
+
+I would laugh if it wasn't sad. And in the end, who cares. Let these people
+worry about making the perfect solutions that will never ship or take years to
+finish because “Early optimization is the root of all evil.” Everybody has their
+definition of fun. I just don't want to listen to people preaching to others how
+to do stuff. If people would just shut up and think before they speak 5% of the
+time, the world would be a different place. But that will never happen. So the
+only solution is to not give a fuck.
+
+This is more a rant than an actual post with some solution, so maybe I am a part
+of the problem. Who knows? Just venting. Every so often it helps.
+
+Do your Rust thing. It's not for me, though. But if it works for you, more power
+to you. Do your project with vanilla JavaScript. You don't always need
+TypeScript, Next.js or who know what else to make a button do a thing. Use VS
+Code or Vim or Emacs or even Notepad if you wish. If you are having fun, then
+just do it. Don't worry about these elitist pricks. They will never be satisfied
+anyway. You will never get their approval. So why even bother. Just go for
+it. Use C, Rust, OCaml, whatever floats your boat. If it tickles you, just do
+it. To hell with everybody else. And if somebody says O(N) complexity, dude? You
+can say, OOOOO, fuck the fuck off.
+
+If this post triggered you, then you are the asshole. Probably. Then you
+probably are that guy preaching about O(N) or this language is soo slow
+haha. Stop it. Nobody cares! Touch grass.
+
+Anyway, back to having fun. Cheers!
diff --git a/_posts/posts/2024-02-11-k-mer.md b/_posts/posts/2024-02-11-k-mer.md
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+---
+title: "Navigating the genome using k-mers for DNA analysis and visualization"
+permalink: /navigating-the-genome-using-k-mers-for-dna-analysis-and-visualization.html
+date: 2024-02-11T01:04:28+02:00
+layout: post
+type: post
+mathjax: yes
+draft: true
+published: false
+---
+
+## Brief introduction to K-mer
+
+A "k-mer" refers to all the possible substrings of length \\(k\\) contained in a
+string, which is commonly used in computational biology and bioinformatics. In
+the context of DNA, RNA, or protein sequences, a k-mer is a sequence of \\(k\\)
+nucleotides (for DNA and RNA) or amino acids (for proteins).
+
+The concept of k-mers is fundamental in various bioinformatics applications,
+including genome assembly, sequence alignment, and identification of repeat
+sequences. By analyzing the frequency and distribution of k-mers within a
+sequence or set of sequences, researchers can infer structural characteristics,
+identify genetic variants, and compare genomic or proteomic compositions between
+different organisms or conditions.
+
+For example, in genome assembly, k-mers are used to reconstruct the sequence of
+a genome from a collection of short sequencing reads. By finding overlaps
+between the k-mers derived from these reads, assembly algorithms can piece
+together contiguous sequences (contigs), which represent longer sections of the
+genome.
+
+The choice of \\(k\\) (the length of the k-mer) is crucial and depends on the
+specific application. A larger \\(k\\) provides more specificity (useful for
+distinguishing between closely related sequences), while a smaller \\(k\\)
+offers greater sensitivity (useful for detecting repeats or low-complexity
+regions). However, the computational resources required increase with \\(k\\),
+as there are \\(4^k\\) possible k-mers for nucleotide sequences (due to the four
+types of nucleotides: A, T, C, G) and \\(20^k\\) for amino acid sequences (due
+to the twenty standard amino acids).
+
+## K-mer counting
+
+K-mer counting is a fundamental process in bioinformatics used for analyzing the
+frequency of k-mers (subsequences of length \\(k\\)) in DNA, RNA, or protein
+sequences. Efficient k-mer counting is crucial for various applications such as
+genome assembly, metagenomics, and sequence comparison. The implementation
+typically involves parsing a sequence into all possible k-mers and then counting
+the occurrences of each unique k-mer. Here's a general approach to implementing
+k-mer counting:
+
+### Reading the Sequences
+
+The first step involves reading the genetic or protein sequences from files,
+which are often in formats like FASTA or FASTQ. These files contain one or
+multiple sequences that will be processed to extract k-mers.
+
+### Generating K-mers
+
+For each sequence, generate all possible subsequences of length \\(k\\). This is
+done by sliding a window of size \\(k\\) across the sequence, one nucleotide (or
+amino acid) at a time, and extracting the subsequence within this window.
+
+### Counting K-mers
+
+The extracted k-mers are then counted. This can be achieved using various data
+structures:
+
+- **Hash Tables (Dictionaries)**: They offer an efficient way to keep track of
+  k-mer counts, with k-mers as keys and their frequencies as values. This
+  approach is straightforward but can become memory-intensive with large
+  datasets or large values of \\(k\\).
+- **Suffix Trees or Arrays**: These data structures are more space-efficient for
+  k-mer counting, especially for large datasets. They allow for efficient
+  retrieval of k-mer occurrences but are more complex to implement.
+- **Bloom Filters and Count-Min Sketch**: For very large datasets, probabilistic
+  data structures like Bloom filters or Count-Min Sketch can estimate k-mer
+  counts using significantly less memory, at the cost of a controlled error
+  rate.
+
+### Handling Memory and Performance Issues
+
+K-mer counting can be memory-intensive, especially for large values of \\(k\\) or
+large datasets. Optimizations include:
+
+- **Compressing K-mers**: Representing k-mers using a binary format rather than
+  strings can save memory.
+- **Parallel Processing**: Distributing the k-mer counting task across multiple
+  processors or machines can significantly speed up the process.
+- **Minimizing I/O Operations**: Efficiently reading and processing sequences
+  from files in chunks reduces I/O overhead.
+
+### Post-processing
+
+After counting, the k-mer frequencies can be used directly for analyses or can
+undergo further processing, such as filtering rare k-mers, which are often
+errors, or normalizing counts for comparative analysis.
+
+### Implementation Example
+
+Here's a simple Python example using a dictionary for k-mer counting:
+
+```python
+def count_kmers(sequence, k):
+    kmer_counts = {}
+    for i in range(len(sequence) - k + 1):
+        kmer = sequence[i:i+k]
+        if kmer in kmer_counts:
+            kmer_counts[kmer] += 1
+        else:
+            kmer_counts[kmer] = 1
+    return kmer_counts
+
+# Example usage
+sequence = "ATGCGATGATCTGATG"
+k = 3
+kmer_counts = count_kmers(sequence, k)
+print(kmer_counts)
+```
+
+This code snippet counts the occurrences of each 3-mer in a given sequence.
+
+For real-world applications, especially those involving large datasets, consider
+using specialized bioinformatics tools like Jellyfish, KMC, or khmer, which are
+optimized for efficiency and scalability.
+
+Now that we have the basics out of the way we can start implementing basic k-mer
+counter in C.
+
+## Implementing sequence reading in C
+
+## Additional reading material
+
+- [2101.08385](https://arxiv.org/pdf/2101.08385.pdf) - Motif Identification using CNN-based Pairwise
+- [2112.15107](https://arxiv.org/pdf/2112.15107.pdf) - Probabilistic Models of k-mer Frequencies
+- [2205.13915](https://arxiv.org/pdf/2205.13915.pdf) - DiMA: Sequence Diversity Dynamics Analyser for Viruses
+- [2209.09242](https://arxiv.org/pdf/2209.09242.pdf) - Computing Phylo-k-mers
+- [2305.07545](https://arxiv.org/pdf/2305.07545.pdf) - KmerCo: A lightweight K-mer counting technique with a tiny memory footprint
+- [2308.01920](https://arxiv.org/pdf/2308.01920.pdf) - Sequence-Based Nanobody-Antigen Binding
+- [2310.10321](https://arxiv.org/pdf/2310.10321.pdf) - Hamming Encoder: Mining Discriminative k-mers for Discrete Sequence Classification
+- [2312.03865](https://arxiv.org/pdf/2312.03865.pdf) - Learning Genomic Sequence Representations using Graph Neural Networks over De Bruijn Graphs
+- [2401.14025](https://arxiv.org/pdf/2401.14025.pdf) - DNA Sequence Classification with Compressors