The target audience for this is people who are beginners at software engineering and using linux. A lot of the information here may be obvious or already known to you. The language involved is C but you do not need to know any C to read this tutorial. I used mg to write this blog post. I used vs code to edit the source code.
This post is also available on gopher://tilde.team:70/0/~river/tweak-free-software
If you use a piece of free software and it's 99% perfect but there's just this one thing it does that annoys the hell out of you.. you can in theory just fix it! Here's a look at what doing that is like. Hopefully it inspires you, or you pick up a could tricks on the way!