I implemented a modern LLM in 700 lines of C

Excerpt

I’ve been working on a small project called gemma4.c. The idea is pretty simple: you can download a modern language model, compile one 700-line C file, and have it generate text on an ordinary CPU. Then you can read that same file from top to bottom and understand exactly how the model generates each new token. The model is Gemma 4 E2B, one of Google’s latest open models. The C runtime handles the tokenizer, transformer, KV cache, sampling, and CPU kernels itself. There’s no inference framework