Awesome JAX

JAX brings automatic differentiation and the XLA compiler together through a NumPy-like API for high performance machine learning research on accelerators like GPUs and TPUs.

This is a curated list of awesome JAX libraries, projects, and other resources. Contributions are welcome!

Be sure to check out our (experimental) interactive web version: https://lockwo.github.io/awesome-jax/.

Why do we need another "awesome-jax" list? Existing ones are inactive, and this is directly based on the no longer active Awesome JAX repos https://github.com/n2cholas/awesome-jax/ and https://github.com/mhlr/awesome-jax.

Contents

• Libraries
• Models and Projects
• Tutorials and Blog Posts
• Community

Libraries

• Neural Network Libraries

  • Flax - Flax is a neural network library for JAX that is designed for flexibility.
  • Equinox - Elegant easy-to-use neural networks + scientific computing in JAX.

• Reinforcement Learning Libraries

  • JaxMARL - Multi-Agent Reinforcement Learning with JAX.
  • Algorithms
    • cleanrl - High-quality single file implementation of Deep Reinforcement Learning algorithms with research-friendly features (PPO, DQN, C51, DDPG, TD3, SAC, PPG).
    • rlax - a library built on top of JAX that exposes useful building blocks for implementing reinforcement learning agents.
    • purejaxrl - Really Fast End-to-End Jax RL Implementations.
    • Mava - 🦁 A research-friendly codebase for fast experimentation of multi-agent reinforcement learning in JAX.
    • Stoix - 🏛️A research-friendly codebase for fast experimentation of single-agent reinforcement learning in JAX • End-to-End JAX RL.
  • Environments
    • pgx - Vectorized RL game environments in JAX.
    • jumanji - 🕹️ A diverse suite of scalable reinforcement learning environments in JAX.
    • gymnax - RL Environments in JAX 🌍.
    • brax - Massively parallel rigidbody physics simulation on accelerator hardware.
    • craftax - (Crafter + NetHack) in JAX. ICML 2024 Spotlight.
    • navix - Accelerated minigrid environments with JAX.
    • JaxGCRL - Goal-Conditioned Reinforcement Learning with JAX.
    • Kinetix - Reinforcement learning on general 2D physics environments in JAX. ICLR 2025 Oral.
    • XLand-MiniGrid - JAX-accelerated Meta-Reinforcement Learning Environments Inspired by XLand and MiniGrid 🏎️.

• Natural Language Processing Libraries

  • levanter - Legible, Scalable, Reproducible Foundation Models with Named Tensors and Jax.
  • maxtext - A simple, performant and scalable Jax LLM!
  • EasyLM - Large language models (LLMs) made easy, EasyLM is a one stop solution for pre-training, finetuning, evaluating and serving LLMs in JAX/Flax.

• JAX Utilities Libraries

  • jaxtyping - Type annotations and runtime checking for shape and dtype of JAX/NumPy/PyTorch/etc. arrays.
  • chex - a library of utilities for helping to write reliable JAX code.
  • mpi4jax - Zero-copy MPI communication of JAX arrays, for turbo-charged HPC applications in Python ⚡.
  • jax-tqdm - Add a tqdm progress bar to your JAX scans and loops.
  • JAX-Toolbox - JAX Toolbox provides a public CI, Docker images for popular JAX libraries, and optimized JAX examples to simplify and enhance your JAX development experience on NVIDIA GPUs.
  • penzai - A JAX research toolkit for building, editing, and visualizing neural networks.
  • orbax - Orbax provides common checkpointing and persistence utilities for JAX users.

• Computer Vision Libraries

  • Scenic - Scenic: A Jax Library for Computer Vision Research and Beyond.
  • dm_pix - PIX is an image processing library in JAX, for JAX.

• Distributions, Sampling, and Probabilistic Libraries

  • distreqx - Distrax, but in equinox. Lightweight JAX library of probability distributions and bijectors.
  • distrax - a lightweight library of probability distributions and bijectors.
  • flowjax - Distributions, bijections and normalizing flows using Equinox and JAX.
  • blackjax - BlackJAX is a Bayesian Inference library designed for ease of use, speed and modularity.
  • bayex - Minimal Implementation of Bayesian Optimization in JAX.
  • efax - Exponential families for JAX.
  • jaxns - Probabilistic Programming and Nested sampling in JAX.

• GPJax - Gaussian processes in JAX.

• tinygp - The tiniest of Gaussian Process libraries.

• Diffrax - Numerical differential equation solvers in JAX. Autodifferentiable and GPU-capable.

• probdiffeq - Probabilistic solvers for differential equations in JAX. Adaptive ODE solvers with calibration, state-space model factorisations, and custom information operators. Compatible with the broader JAX scientific computing ecosystem.

• jax-md - Differentiable, Hardware Accelerated, Molecular Dynamics.

• lineax - Linear solvers in JAX and Equinox.

• optimistix - Nonlinear optimisation (root-finding, least squares, etc.) in JAX+Equinox.

• sympy2jax - Turn SymPy expressions into trainable JAX expressions.

• quax - Multiple dispatch over abstract array types in JAX.

• interpax - Interpolation and function approximation with JAX.

• quadax - Numerical quadrature with JAX.

• optax - Optax is a gradient processing and optimization library for JAX.

• dynamax - State Space Models library in JAX.

• dynamiqs - High-performance quantum systems simulation with JAX (GPU-accelerated & differentiable solvers).

• scico - Scientific Computational Imaging COde.

• exojax - 🐈 Automatic differentiable spectrum modeling of exoplanets/brown dwarfs using JAX, compatible with NumPyro and Optax/JAXopt.

• PGMax - Loopy belief propagation for factor graphs on discrete variables in JAX.

• evosax - Evolution Strategies in JAX 🦎.

• evojax - EvoJAX is a scalable, general purpose, hardware-accelerated neuroevolution toolkit. Built on top of the JAX library, this toolkit enables neuroevolution algorithms to work with neural networks running in parallel across multiple TPU/GPUs.

• mctx - Monte Carlo tree search in JAX.

• kfac-jax - Second Order Optimization and Curvature Estimation with K-FAC in JAX.

• jwave - A JAX-based research framework for differentiable and parallelizable acoustic simulations, on CPU, GPUs and TPUs.

• jax_cosmo - A differentiable cosmology library in JAX.

• jaxlie - Rigid transforms + Lie groups in JAX.

• ott - Optimal transport tools implemented with the JAX framework, to get differentiable, parallel and jit-able computations.

• XLB - XLB: Accelerated Lattice Boltzmann (XLB) for Physics-based ML.

• EasyDeL - Accelerate, Optimize performance with streamlined training and serving options with JAX.

• QDax - Accelerated Quality-Diversity.

• paxml - Pax is a Jax-based machine learning framework for training large scale models. Pax allows for advanced and fully configurable experimentation and parallelization, and has demonstrated industry leading model flop utilization rates.

• econpizza - Solve nonlinear heterogeneous agent models.

• fedjax - FedJAX is a JAX-based open source library for Federated Learning simulations that emphasizes ease-of-use in research.

• neural-tangents - Fast and Easy Infinite Neural Networks in Python.

• jax-fem - Differentiable Finite Element Method with JAX.

• veros - The versatile ocean simulator, in pure Python, powered by JAX.

• JAXFLUIDS - Differentiable Fluid Dynamics Package.

• klujax - Solve sparse linear systems in JAX using the KLU algorithm.

• coreax - A library for coreset algorithms, written in Jax for fast execution and GPU support.

• fdtdx - Electromagnetic FDTD Simulations in JAX.

• Jaxley - Differentiable neuron simulations with biophysical detail on CPU, GPU, or TPU.

• torch2jax - Wraps PyTorch code in a JIT-compatible way for JAX. Supports automatically defining gradients for reverse-mode AutoDiff.

• cola - Compositional Linear Algebra.

• laplax - Laplace approximations in JAX.

• thrml - Thermodynamic Hypergraphical Model Library.

• astronomix - differentiable (magneto)hydrodynamics for astrophysics in JAX.

• memax - Deep memory and sequence models in JAX.

• JAXMg - JAXMg: A multi-GPU linear solver in JAX.

• exponax - Efficient Differentiable n-d PDE Solvers in JAX.

Up and Coming Libraries

• traceax - Stochastic trace estimation using JAX.
• graphax - Cross-Country Elimination in JAX.
• cd_dynamax - Extension of dynamax repo to cases with continuous-time dynamics with measurements sampled at possibly irregular discrete times. Allows generic inference of dynamical systems parameters from partial noisy observations via auto-differentiable filtering, SGD, and HMC.
• jumpax - Jump Processes in JAX.
• driftax - Drifting Generative Models - JAX/Flax implmentation of Generative Modeling via Drifting.
• ParamRF - Parametric Radio Frequency Modelling, Fitting and Sampling.

Inactive Libraries

• Haiku - JAX-based neural network library.
• jraph - A Graph Neural Network Library in Jax.
• SymJAX - symbolic CPU/GPU/TPU programming.
• coax - Modular framework for Reinforcement Learning in python.
• eqxvision - A Python package of computer vision models for the Equinox ecosystem.
• jaxfit - GPU/TPU accelerated nonlinear least-squares curve fitting using JAX.
• safejax - Serialize JAX, Flax, Haiku, or Objax model params with 🤗safetensors.
• kernex - Stencil computations in JAX.
• lorax - LoRA for arbitrary JAX models and functions.
• mcx - Express & compile probabilistic programs for performant inference on CPU & GPU. Powered by JAX.
• einshape - DSL-based reshaping library for JAX and other frameworks.
• sklearn-jax-kernels - Composable kernels for scikit-learn implemented in JAX.
• deltapv - A photovoltaic simulator with automatic differentiation.
• cr-sparse - Functional models and algorithms for sparse signal processing.
• flaxvision - A selection of neural network models ported from torchvision for JAX & Flax.
• imax - Image augmentation library for Jax.
• jax-unirep - Reimplementation of the UniRep protein featurization model.
• parallax - Immutable Torch Modules for JAX.
• jax-resnet - Implementations and checkpoints for ResNet, Wide ResNet, ResNeXt, ResNet-D, and ResNeSt in JAX (Flax).
• elegy - A High Level API for Deep Learning in JAX.
• objax - Objax is an open source machine learning framework that accelerates research and learning thanks to a minimalist object-oriented design and a readable code base.
• jaxrl - JAX (Flax) implementation of algorithms for Deep Reinforcement Learning with continuous action spaces.

Models and Projects

• whisper-jax - JAX implementation of OpenAI's Whisper model for up to 70x speed-up on TPU.
• esm2quinox - An implementation of ESM2 in Equinox+JAX.

Tutorials and Blog Posts

• Learning JAX as a PyTorch developer
• Massively parallel MCMC with JAX
• Achieving Over 4000x Speedups and Meta-Evolving Discoveries with PureJaxRL
• How to add a progress bar to JAX scans and loops
• MCMC in JAX with benchmarks: 3 ways to write a sampler
• Deterministic ADVI in JAX
• Exploring hyperparameter meta-loss landscapes with Jax
• Evolving Neural Networks in JAX
• Meta-Learning in 50 Lines of JAX
• Implementing NeRF in JAX
• Normalizing Flows in 100 Lines of JAX
• JAX vs Julia (vs PyTorch)
• From PyTorch to JAX: towards neural net frameworks that purify stateful code
• out of distribution detection using focal loss
• Differentiable Path Tracing on the GPU/TPU
• Getting started with JAX (MLPs, CNNs & RNNs)

Videos

• The State of the JAX Ecosystem in 2025
• NeurIPS 2020: JAX Ecosystem Meetup
• Introduction to JAX
• JAX: Accelerated Machine Learning Research | SciPy 2020 | VanderPlas
• Bayesian Programming with JAX + NumPyro — Andy Kitchen

Community

• JAX LLM Discord