mind uploading

Inigo Quilez live-codes a cartoon character painting entirely from math, using signed distance fields in a Shadertoy shader. He explains each step of building the image from formulas.

Bisqwit builds a Doom or Duke Nukem 3D style software-rendered 3D engine in C from scratch, supporting non-Euclidean geometry. It covers vector rotation and portal rendering with sped-up, tool-assisted coding.

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.