Apple has released macOS 27 developer beta 4, following closely behind the public beta and a revised version of beta 3. This new developer release is expected to become macOS 27 public beta 2 in the coming days, assuming no major bugs are found.

macOS 27 Golden Gate beta 3 had addressed reliability issues from beta 2 and introduced new wallpapers and screensavers. The latest beta, macOS 27 Golden Gate, brings significant improvements to Liquid Glass, allowing users to adjust UI element transparency. It also standardizes rounded corners across the system, a change requested by users after macOS 26.

Furthermore, macOS 27 Golden Gate introduces a new Siri AI that utilizes a novel indexing system for more accurate responses. This AI and the OS update rely on the third-generation Apple Foundation Models. The build version for this beta is 26A5388g. Installation involves backing up your Mac, navigating to System Settings > General > Software Update, and selecting the macOS Developer Golden Gate Beta from the Beta Updates dropdown.