Yes, and I would typically search for simple projects using keywords such as “micro”, “small”, “tiny”, or “pico”.

I would then try to re-implement the “getting started” code in the readme from scratch, like a little programming puzzle. If I can’t figure it out, I‘ll add in some debugger breakpoints, inspect the stack trace to understand how it works, then code the needed methods / classes as I go.

If you’re a ruby programmer, soveran’s work in github can be read in a day or two. I specifically like cuba (micro webframework) and mote (microtemplate).