LESSON 2.9 · Assessment · 180 min

Mastery Gate 2: build minBPE + makemore

Mastery Gate 2: build minBPE + makemore. Learn the complete tokenizer and language-model loop and complete: Train on unseen data, evaluate, and explain failure cases. Part of the “

Learning objectives

  1. Explain what problem “Mastery Gate 2: build minBPE + makemore” solves without hiding behind terminology.
  2. Trace the variables and causal links across the complete tokenizer and language-model loop.
  3. Complete “Train on unseen data, evaluate, and explain failure cases” and judge the result with evidence rather than intuition.

Core concepts

the complete tokenizer and language-model loop

the complete tokenizer and language-model loop is part of the lesson’s causal model. State its inputs, outputs, invariants, and failure mode; then verify it with a hand-check or a minimal experiment before moving to an optimized implementation.

Build and verify

Train on unseen data, evaluate, and explain failure cases

  • Predict: write the expected output, trend, or failure before running code.
  • Build: implement only the minimum components needed to answer the question.
  • Verify: compare with a baseline or trusted implementation; save seeds, parameters, and raw outputs.
  • Transfer: change one shape, dataset, scale, or workload condition and explain whether the conclusion still holds.

Open the complete interactive lesson