14 / Experiments & systems

next-char-model

AI

A language model dismantled into pieces small enough to understand, train, and rebuild.

next-char-model is a pedagogical project that progressively builds a small character prediction model, moving from embeddings toward multi-head attention and transformer-style blocks.

The problem

A complete transformer combines several mechanisms that are difficult to inspect at once. This project introduces them through a sequence of small scripts.

Design & implementation

Numbered scripts introduce the parts of a small autoregressive model: tokenization, embeddings, positions, attention, projections, residual connections, MLP layers, layer normalization, and then multi-head attention.

The project also includes embedding visualizations and a saved checkpoint, making it possible to move from learning code to a small loop of generation and inspection.

What it does

  • Pedagogical PyTorch character-level language model
  • Explicit progression from embeddings to blocks with multi-head attention
  • Embedding visualizations before and after training
  • Loading and reuse of a saved checkpoint