Developer: K-D Lab
Release Date: May 21, 2004
Source Code Release Date: June 4, 2021

Perimeter is a mid-2000's RTS game set in a science fiction universe in the distant future. The game has a focus on terraforming, energy production, and the ability to protect your installations with an energy barrier, the namesake Perimeter.

The original game Perimeter was released in 2004 and an expansion pack, Emperor's Testament, was released in 2005. The developer released the source code to the game in 2021 and released a version on Steam in 2024 called Perimeter: Legate Edition. All three are compatible with the source port.

Note that at this time the Mac support from the source port is considered experimental so I'm labeling this one Early Access. It runs on Apple Silicon Macs with the latest macOS but I have had limited ability to test it elsewhere so your mileage may vary. If you can't get it to launch you can report a bug to me. If the game runs but something in it doesn't function correctly, the developer's GitHub repo might be a more useful spot to report it.

  Buy Perimeter on GOG.com

  Buy Perimeter on the Humble Store