exo
Run frontier AI locally.
exo: pooling Macs to run bigger models at home
A Python project that joins several devices into one AI cluster so models larger than a single machine can run locally, with automatic discovery and a Thunderbolt networking option.
The pitch
The GitHub description is two words: run frontier AI locally. exo does that by connecting all of your devices into an AI cluster, which lets you run models larger than would fit on a single device. The README adds a detail that shapes the whole project: day 0 support for RDMA over Thunderbolt, which means models run faster as you add devices. The project is Python under the Apache-2.0 license and has grown past 46,000 stars.
The headline features
The feature list leans on hardware you might already own. Automatic device discovery needs no manual configuration. RDMA over Thunderbolt is described with a claimed 99 percent latency reduction. Topology aware auto parallel splits models based on a real time view of device topology, and tensor parallelism comes with claimed speedups on 2 and 4 devices. MLX is used as the inference backend, which points the project squarely at Apple silicon.
The benchmarks
The benchmarks section cites runs on 4 M3 Ultra Mac Studio units with tensor parallel RDMA, covering models such as Qwen3 in 8 bit, DeepSeek v3.1 in 8 bit, and Kimi K2 Thinking in native 4 bit. Worth noting is where these numbers come from: the source is attributed to a third party video about a large VRAM Mac setup, not to the maintainers' own lab. That attribution matters when reading the speedup claims.
Getting it running on macOS
The quick start describes a mostly hands off setup. Devices running exo automatically discover each other, and each device provides an API and a dashboard at a local address. Running from source on macOS requires Xcode for the Metal ToolChain and brew for package management, with a note about accepting a binary cache to avoid building the Xcode Metal ToolChain. The tradeoff is laid out up front, which is more than many projects bother to do.
Community notes