If you're interested in software archaeology or Processing, you'll enjoy Bonnie's exploration of an eternal question: is Processing, in fact, Java? If not Java, what is it?
An interactive exploration into a math-y rabbit hole that began when Patrick decided he didn't want his animated trains to look like they were colliding.
Jamie was writing a SQL query compiler. Writing a compiler is a great way to get acquainted with all the weird nooks and crannies of a language. He has documented some for our reading pleasure.
An interactive debugger for Ruby with a beautiful terminal UI.
What do you do after you buy three shopping bags worth of Fiber Channel cards on eBay? This is a delightful story of the rabbit hole Ben went down to make the cards useful, including writing a virtual device handler that treats the cards like SCIS scanners!
An interactive Sudoku solver that lets you step forward and backward through a visualization of how it works.
Tired of the same old dystopias that stomp free speech/freedom of movement? Randomized Dystopia suggests other rights your fictional tyranny could deny its citizens! A Flask app remixing statements of human rights, children's rights, and women's rights. (source: https://gitlab.com/brainwane/randomized-dystopia)
SOIE is a GUI application written in Python and C++ for the interactive exploration of simulations of self-organizing active particles. Roujia's paper is here: https://www.roujiawen.com/portfolio/pdfs/interactive_evolution.pdf
As the docs note, "Sadly, a lot of today’s open data is trapped in PDF tables."
Mary wrote a little Lisp and then annotated the source code. If you've never written an interpreter for a programming language before, this is a great place to start.