llm.c is a minimalist, systems-level implementation of a small transformer-based language model in C that prioritizes clarity and educational value. By stripping away heavy frameworks, it exposes the core math and memory flows of embeddings, attention, and feed-forward layers. The code illustrates how to wire forward passes, losses, and simple training or inference loops with direct control over arrays and buffers. Its compact design makes it easy to trace execution, profile hotspots, and understand the cost of each operation. Portability is a goal: it aims to compile with common toolchains and run on modest hardware for small experiments. Rather than delivering a production-grade stack, it serves as a reference and learning scaffold for people who want to “see the metal” behind LLMs.

Features

  • Compact C implementation that demystifies transformer internals
  • Embedding, attention, and MLP layers written in a readable style
  • Simple training and sampling loops to experiment end to end
  • Minimal dependencies and portable build targets
  • Transparent memory layout for profiling and optimization practice
  • Command-line usage to run tiny demos and inspect outputs

Project Samples

Project Activity

See All Activity >

License

MIT License

Follow llm.c

llm.c Web Site

Other Useful Business Software
Full-stack observability with actually useful AI | Grafana Cloud Icon
Full-stack observability with actually useful AI | Grafana Cloud

Our generous forever free tier includes the full platform, including the AI Assistant, for 3 users with 10k metrics, 50GB logs, and 50GB traces.

Built on open standards like Prometheus and OpenTelemetry, Grafana Cloud includes Kubernetes Monitoring, Application Observability, Incident Response, plus the AI-powered Grafana Assistant. Get started with our generous free tier today.
Create free account
Rate This Project
Login To Rate This Project

User Reviews

Be the first to post a review of llm.c!

Additional Project Details

Operating Systems

Linux, Mac, Windows

Programming Language

Python

Related Categories

Python Large Language Models (LLM)

Registered

2025-10-15