Felix Codes

At some point I developed an interest in programming language implementation. Guess it seemed natural to learn how my tools actually worked. Most of my research went into existing languages:

Along the way I also came up with stranger experiments:

And adjacent topics:

It all started with a tutorial I wrote in 2009 to make some things more clear to myself, and culminated in 2016 with my interpreter construction book. Since then I wrote more articles about this subject, that you'll find linked from the pages of specific projects.

Why code matters, in one small comic strip

A very comprehensive and precise spec

See also: There's No Such Thing as "No Code".

Fun fact

What's the largest number of different languages you ever used in a single software project? My personal record is 5. In the same file. That is,

Yep, I was young and didn't know any better.


Fun little languages (not mine):




Shell script



Perl / Awk


The Grug Brained Developer: A layman's guide to thinking like the self-aware smol brained

Awesome compilers (Compilers, Interpreters, Runtimes and VMs) A curated list of awesome resources, learning materials, tools, frameworks, platforms, technologies and source code projects in the field of Compilers, Interpreters and Runtimes. This list has a bias towards education.

Just write the #!%/* parser: Writing parsers from scratch. Why simpler is better and why you don't need a parser generator.

And a few about Lisp:

The linklog was moved to its own page after growing too large.