Local AI and Local Models107 · Module III · Lesson 10 of 11
Article · 12 min

llama.cpp

The engine underneath most of it.

Summary

llama.cpp is the C++ engine that runs GGUF-quantized models on nearly any hardware. Ollama, LM Studio, Jan, and half the local-AI ecosystem sit on top of it. Understanding llama.cpp is understanding the substrate.

Objectives
  • 01Build and run llama.cpp from source.
  • 02State the hardware backends it supports.
  • 03Name three tools that wrap it.
The Lesson

The engine

C++ library implementing transformer inference with GGUF quantization. Backends: CPU (AVX2, AVX-512, NEON), CUDA, Metal, Vulkan, ROCm, SYCL. Ships with a server binary that exposes an OpenAI-compatible API. Fast, portable, lean.

The ecosystem

Ollama, LM Studio, Jan, GPT4All, koboldcpp, text-generation-webui, LocalAI — all use llama.cpp as their inference core. The Hugging Face GGUF ecosystem exists because of it. When llama.cpp adds a feature (new quantization, new architecture), the whole ecosystem gains it.

Key Ideas
  • llama.cpp is the substrate under local inference.
  • Learning llama.cpp is learning why every local tool behaves the way it does.