macOS 27
macOS Tahoe on macOS 27
NotNotch is meant to run macOS Tahoe on macOS 27 (Darwin 27) while still supporting macOS 14. The current Xcode 26 toolchain still ships a macOS 26 SDK while the app is expected to run on Darwin 27.
Last updated 2027-06-24
Runtime vs SDK
Local builds may still use the macOS 26 SDK in Xcode 26. The goal is a clean run on macOS 27, not a 27-only app.
What stays the same
macOS Tahoe should keep the same user-facing behavior. The current Xcode 26 toolchain still ships a macOS 26 SDK while the app is expected to run on Darwin 27.