Half-Life on old Macs | Matthew Deaves

A cut-out render of Gordon Freeman running with a crowbar, the mod installer's About picture

Half-Life for old Macs is Half-Life 1 as one universal Half-Life.app, built on the open-source Xash3D FWGS engine in place of the retail GoldSrc one. One download runs natively on everything from a 1999 G3 on Mac OS X 10.3.9 to an M-series Mac on macOS 26, configures itself for the machine it lands on, and plays 25 Half-Life mods as well as the base game. It was built with AI (Claude Code) under my direction and tested on the machines, not an emulator.

Install is copying Half-Life.app into a folder and dropping your own retail valve/ folder beside it. No game content is included. A second app installs the mods, fetching those with a public release from wherever their authors published them, and they show up under Custom Game in the main menu.

The opening tram ride through a service tunnel in Half-Life, lit by a single fluorescent tube — The opening tram ride

The Black Mesa Research Facility lobby with scientists at the reception desk — The Black Mesa lobby

A Sector C security desk under red alert lighting, with a guard seated and a scientist running past — Sector C under a red alert

An outdoor canyon of red rock with hazard barrels and a bunker entrance under a blue sky — Outside on the surface

A concrete dam and roadway cut into red cliffs, with a Danger Machinery sign — The dam

A floating rock island in Xen topped with tall organic spires, against a green and purple nebula — Xen

A wide view across Xen with floating platforms and spires receding into a coloured sky — Across Xen

The Half-Life Mods window on Mac OS X 10.4 Tiger, downloading Xen Warrior with a log of mods that have had their game code added — The mod installer on Tiger, downloading Xen Warrior

The download is on the releases page, and the project page has the rest: which Macs get which CPU slice, what the launcher sets up on each machine, how the mods work and the full credits.