Learn bydoing, not reading.
Developer foundations
The tools every engineer reaches for daily — learned by using them, not reading about them.
Git, by doing
From your first commit to rebasing, rewriting and force-pushing safely — in a live repository that animates every command you type.
The command line
Navigate, create, move and search files, chain commands with pipes and read permissions — on a live file system that redraws as you type.
SQL, by doing
Real SQLite in your browser. Watch rows fly into results, pair up in joins, fall into GROUP BY buckets — and see an index skip the scan.
Regex, visually
Write a pattern and watch it match live, drawn as a railroad diagram the engine visibly walks — until regular expressions finally read like English.
Docker & containers
Pull images, run containers, wire ports and volumes, and build images layer by layer — on a simulated host that shows exactly what's running.
Building with AI
What actually happens inside a language model and a retrieval pipeline, with the dials in your hands.
LLMs, under the hood
Tokens and what they cost, next-token probabilities, temperature, top-k and top-p, and the context window — with real tokenization and a language model small enough to run in your tab.
RAG & vector search
Chunk documents, embed them, search by meaning, rerank, and build the prompt — on a live map of embedding space computed with a real model.
Learn on
YouTube too.
The same hands-on approach, as video. Watch a full build from parts to working result, then subscribe for the next one.
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