computation

David Beazley's PyCon 2019 tutorial derives the lambda calculus from the ground up in Python, using only single-argument functions. He builds booleans, numerals and more with no other language features.

Inigo Quilez live-codes the "Happy Jumping" animated scene in a Shadertoy GLSL shader over about six hours. He builds the raymarched character step by step, explaining the math and procedural techniques, with checkpoints linked for each stage.