exo
by Exo Labs · Application · also known as exo-explore, exo labs
Open-source software that pools several Apple Silicon Macs (and Linux hosts) into one local inference cluster, sharding large models across devices with MLX
Overview
exo is an open-source project from Exo Labs (Apache 2.0) that connects multiple everyday devices into a single cluster for running large language models locally. Devices on the same network, or linked by Thunderbolt cables, discover each other automatically; exo builds a live view of the topology, including memory, link latency and bandwidth, and splits a model across nodes so that models too large for any one machine can still run. It supports tensor parallelism across devices and, on recent macOS versions, RDMA over Thunderbolt 5 to cut inter-node latency.
The inference backend is MLX with MLX distributed for communication, so Apple Silicon Macs are the primary target; Linux hosts currently run on CPU, with GPU support described as in development. A macOS app and a web dashboard manage the cluster and offer a chat interface, models load from the Hugging Face Hub, and the server exposes OpenAI Chat Completions, OpenAI Responses, Claude Messages and Ollama-compatible endpoints so existing clients work unchanged. Published examples run very large open-weight models across four Mac Studios.
exo is under rapid development: the repository is active daily, all nodes must run the same version, and APIs and installation steps change often. It is well suited to experimenters with several Macs who want to run models beyond a single machine's memory, less so to teams needing a stable, supported serving stack.
Editorial note on uncertainty. The project is pre-1.0 in its source tree and changes quickly; capabilities described reflect the README on 2026-11-02 and may shift. Exo Labs also lists a business offering but publishes no pricing.
Capabilities
- Automatic device discovery over LAN or Thunderbolt
- Topology-aware model sharding and tensor parallelism
- MLX inference backend with MLX distributed communication
- OpenAI-, Claude- and Ollama-compatible API endpoints
- Web dashboard and macOS app for cluster management
- Model loading from the Hugging Face Hub
Typical workflows
- Run a model larger than one Mac's memory across several Macs
- Point an OpenAI-compatible client at a home cluster
- Benchmark Thunderbolt versus Ethernet interconnects
Strengths
- Uses hardware already owned instead of a GPU server
- Open source with a permissive license
- Drop-in API compatibility with common clients
Limitations
- Apple Silicon-centric; Linux is CPU-only for now
- Fast-moving project with frequent breaking changes
- All nodes must run identical versions
- No long-term support or stability guarantees
Prerequisites
- Two or more Apple Silicon Macs on one network (macOS 15.1 or later for the app)
- Fast interconnect for good performance
Who it is for
- Experimenters with several Macs
- Researchers exploring distributed local inference
Alternatives & comparison
- llama.cpp
C/C++ inference engine for LLMs and vision-language models with GGUF quantized weights, Metal, CUDA, Vulkan and other backends, a CLI and an OpenAI-compatible server
Open sourceOpen source - MLX LM
Python package and CLI for running, serving, quantizing and fine-tuning large language models on Apple Silicon with MLX
Open sourceOpen source - Ollama
Open-source runtime and model manager for running open-weight LLMs locally on macOS, Windows and Linux, with a REST API, OpenAI- and Anthropic-compatible endpoints and optional cloud models
Open sourceOpen source - vLLM
High-throughput LLM inference and serving engine with PagedAttention, continuous batching, quantization and an OpenAI-compatible server for GPU and accelerator clusters
Open sourceOpen source
Sources & verification
Primary sources consulted for this record. Claims are tied to the fields each source supports; the automated link checker re-verifies every URL on a schedule.
- Licensehttps://github.com/exo-explore/exo/blob/main/LICENSEchecked Nov 1, 2026
Supports: license_spdx, source_model
- Official sitechecked Nov 1, 2026
- Official siteexo-explore/exo READMEchecked Nov 1, 2026
https://github.com/exo-explore/exo
Supports: name, summary, capabilities, limitations, prerequisites
- Confidence
- Medium
- Reviewed
- Nov 1, 2026
- Links
- Verified · Nov 2, 2026
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