Open Source Inference Engines for LLMs

  • Last Updated 9 August, 2026
  • by David Spuler, Ph.D.

What are Open-Source Frameworks?

AI inference for an LLM requires an engine. There are many open source LLMs available online, notably from Meta and Mistral, but they need an engine to run. Fortunately, there are multiple open-source full implementations of Transformer engines that can run inference for an LLM.

List of Open Source Inference Frameworks

Many examples are listed below and it's quite an overwhelming group. Most "famous" are PyTorch and TensorFlow, but there are many others with a stack. There are also several new fully-coded inference-specific engines, which don't have much training capability. Some of these frameworks are ML compilers (e.g. XLA and MLIR). There are also several frameworks that have gained a reputation for running RAG architectures, such as LangChain and Ollama.

These frameworks are mostly offered with permissive and non-copyleft licenses that allow commercial usage (review each package for its license details).

Here's the list so far:

  • PyTorch
  • TensorFlow
  • LangChain
  • TensorRT (NVIDIA)
  • ROCm (AMD)
  • GGML
  • Llama.cpp
  • MLIR (LLVM)
  • Ollama
  • LLMFarm
  • Llama2.c
  • OpenVINO (Intel)
  • Transformers (Hugging Face)
  • FasterTransformer (NVIDIA)
  • vLLM
  • TGI (Text Generation Inference) (Hugging Face)
  • MXNet
  • CTranslate2
  • DeepSpeed/DeepSpeed-MII
  • OpenLLM
  • RayServe
  • tinygrad
  • MLX (Apple)
  • TinyChatEngine

ML compilers (graph compilers) that are open source:

  • ONNX (Industry coalition)
  • TVM (Apache)
  • MLC LLM
  • XLA (TensorFlow)

And some non-open source inference platforms:

  • CUDA (NVIDIA)
  • AICore (Google)
  • MediaPipe (Google)

Inference Frameworks: Book Excerpts and Blog Articles

Free online book excerpts with full text chapters online and free PDF downloads, and the Aussie AI blog, including related articles:

  • Open Source Models: There are many different AI models that have been open-sourced. In many cases, both the code for the inference algorithm and the model's weights are available. Some licenses have only minimal restrictions (e.g. MIT License, Apache License 2.0), whereas other model licenses restrict usage to research or non-commercial activities.... more about Open Source Models »
  • Inference frameworks are software platforms that take a model and execute it against requests from users. Many inference frameworks also provide training and fine-tuning capabilities, but not all do. Many frameworks have been open-sourced, but there are also many that remain proprietary, and there is much competition occurring in the space. ... more about Inference frameworks »
  • David Spuler, March 2024, Generative AI in C++: Coding Transformers and LLMs, https://www.aussieai.com/book/toc PDF: https://www.aussieai.com/pdf/BOOK-Generative-AI-CPP-Spuler-2024.pdf

Research on Inference Frameworks

Industry articles. Online blog articles and industry press releases on inference frameworks:

Research papers. Academic papers about inference frameworks, with evaluations or theoretical aspects:

Benchmarking papers. Various research papers with performance measurement and benchmarking of inference frameworks:

More AI Research

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