RavynOS, a pre-alpha open source operating system built on Darwin, FreeBSD and Apple's open source code, aims to deliver macOS's interface and workflows without Apple's hardware restrictions, according to the project's website.
The project says it remains in developer preview and is explicit that it is "not polished, not completed, and not ready for end users yet."
RavynOS supports key Cocoa APIs so developers can port existing macOS Cocoa applications with minimal changes, and it replicates familiar macOS interface elements including a global menu bar, Command-key shortcuts and the standard folder hierarchy, according to the site.
Development is led by RavynSoft, with contributions coordinated through Discord and GitHub, the project said.
An open source, non-Apple path for running Mac software is a niche bet since most developers are not migrating off macOS. But a pre-alpha OS that already runs Cocoa apps with minimal porting effort is further along than most clean-room compatibility layers ever get, and worth watching if it reaches a usable release.