Show HN: Kakehashi – Experimental userspace to run macOS binaries on Linux ARM
Points and comments are a snapshot, not live.
Kakehashi is an experimental userspace translation layer that runs macOS ARM64 CLI binaries on Linux aarch64.
Kakehashi loads Darwin Mach-O binaries on Linux aarch64, maps a freestanding libSystem, and translates BSD syscalls. It runs 7-Zip (multi-threaded, ~5.2x slower than native), curl (200+ commands passing), and basic Git. The project targets CI cost savings: macOS runners cost ~10-12x more per minute than Linux ARM. Kakehashi operates without kernel modules or root, using Rust. Performance tax is at the syscall boundary, not instruction emulation. Future goals include full Xcode Tools support and macOS Homebrew.
What commenters are saying
The author confirmed the project was developed with LLM assistance (Grok 4.5) over about 6 days. Commenters asked about Darling (the prior art) and clean-room concerns; the author stated Kakehashi is written from scratch in Rust with a different architecture (pure userspace vs Darling's kernel approach). Several expressed interest in running macOS plugins for music production or building iOS apps on Linux ARM runners. The cost-saving CI use case resonated. Questions arose about supporting different macOS target versions and whether GUI support is planned.