cider

Cider is a runtime environment for macOS applications on Linux, forked from Darling and licensed under GPLv3 or later. It runs Mach-O binaries directly on the Linux kernel through its own dyld, libSystem, and kernel-emulation layer, with no virtual machine and no Apple kernel. The project is in an early state: command-line software works, but most GUI applications do not. Automated checks in the repository verify a shell, booting through launchd, Nix running inside the container, JavaScriptCore, libdispatch, Security, CoreAudio, scripting bridges, a trivial AppKit window on Wayland, and a guest binary reaching a Wayland compositor. The GUI backend is Wayland only; there is no X11 or DISPLAY fallback. LibreOffice is documented as rendering, accepting keyboard and mouse input, resizing, opening menus and file dialogs, and inserting a picture, though this is driven manually rather than by an automated check. Cider builds with Nix and Buck2. Nix is the only supported packaging method; there is no distribution package or tarball. A full build is large, and a minimal build that drops GUI frameworks, private frameworks, and scripting languages is available. Installation is supported on NixOS through a module or elsewhere via the nix profile install command. Cider uses CIDERPREFIXes, similar to WINEPREFIXes: virtual chroot-like environments with a macOS-shaped filesystem where software can be installed safely. The default prefix is ~/.cider, configurable via the CIDERPREFIX environment variable. Prefixes rely on overlayfs and therefore cannot live on NFS or eCryptfs, and the default location will not work with an encrypted home directory. The repository is organized into guest-side Darwin sources, host-side Linux sources, Buck2 rules and toolchains, vendored upstream components, Nix packaging, and nushell-based developer scripts. Development can be done without Nix by driving Buck2 directly after obtaining the toolchain, which enables fast rebuilds after editing a single file.