diff --git a/mkfile b/mkfile
new file mode 100644
index 0000000000000000000000000000000000000000..03330cecb4f41b15ea8ba62c3b57b91a98c9e37e
--- /dev/null
+++ b/mkfile
@@ -0,0 +1,5 @@
+</$objtype/mkfile
+
+run:
+    $CC $CFLAGS tree.c
+    $LD $LDFLAGS -o tree tree.$O