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AI learning

AI learning

Build the model. Test the guardrails.

Learn how language models train, how retrieval grounds an answer, and how to keep AI-assisted changes within a tested boundary. Start with a free project and leave with working files you can inspect, change and keep.

Two free projects. Real work to take away.

No login, installation or API key required.

Make your own LLM

Build a tiny neural next-token model in JavaScript. Follow the numbers from tokens to predictions, gradients and changed weights.

  • Tokenize a corpus and learn embeddings.
  • Check your gradients and measure loss on held-out text.
  • Generate text, save your trained weights and restore the model.
You keep

Your browser app, trained checkpoint, tokenizer and experiment notes.

Bring JavaScript functions, arrays and basic algebra. This is a small teaching model; it does not produce a general-purpose chatbot.

Train your model

Agentic guardrails

Turn a plausible AI code proposal into a change you can trust enough to review. Set the scope, find the defect and prove the repair preserves valid behavior.

  • Write an issue, repository instructions and permission rules.
  • Catch a bad proposal with your own regression test.
  • Review changed files, stale evidence and an unfamiliar handoff.
You keep

A repository ZIP with your app, tests, CLAUDE.md, settings and review notes.

Bring basic JavaScript. Your exported folder is prepared for Claude Code; that optional tool is separate from this browser project.

Build your guardrails

Go deeper with the full courses

Both subjects are included in Web, Plus and Pro.

LLM & RAG engineering

Connect model foundations and training to retrieval, grounded answers and evaluation. Practice access control and failure analysis so an answer is supported by evidence the user is allowed to see.

Model foundations · Training · Retrieval · Evaluation · Access control

Agentic programming

Design tasks and context for AI-assisted work, control tools and permissions, and verify what actually happened. Trace bounded execution and review completion against the requested outcome.

Task design · Context · Tools · Permissions · Verification · Traces

Theory & reasoning — read explanations, predict behavior and examine failure cases before committing to a design.

Hands-on coding — implement a change, run checks, inspect the evidence and tackle a changed problem.