Project catalog
Every project is a real tool split into stages. Explore the catalog or tell us what you need for a personal shortlist.
22 projects
Build and train a neural network from first principles: forward pass, loss functions, and gradient descent optimization.
Python · TypeScript
Your first contact with lexers and grammars. Tokenize, build the tree and fail with useful errors.
TypeScript · Python · Go · Java
Learn the core foundations of AI coding assistants from scratch: model basics, API key security, why use OpenRouter as a universal model router, tool schemas, and the autonomous ReAct loop.
Python · TypeScript
Read stdin, filter by pattern and honour exit codes. The gateway to Unix tooling.
Go · Python · Zig
Rotations, padding and the compression block. Sign and verify messages without touching a crypto library.
C · Python · Go
Build and parse UDP packets bit by bit. Resolve names by walking the hierarchy from the root servers.
Go · Rust · Python
Vectors, intersections and materials. Write a PPM and watch a scene appear pixel by pixel.
C++ · Rust · TypeScript
From raw bytes to a 200 response. Parse requests, manage connections and serve concurrent traffic.
Go · Python · C · Rust
Build a Model Context Protocol server from scratch with JSON-RPC, tools, and resources.
TypeScript · Python · Go
Implement the RESP protocol, an event loop and key expiry. A real server that talks to redis-cli.
Go · Rust · Python
fork, exec, pipes and redirection. Build a POSIX command interpreter that runs real programs.
C · Rust · Go · Zig
From the expression to the automaton. Backtracking, groups and character classes without your language's regex.
TypeScript · Python · Rust