RimWorld 1.7 beta moves from Unity to in-house Waylith Engine

Ludeon Studios announced RimWorld 1.7, which moves the 2018 simulation game from the Unity engine to the Waylith Engine, an in-house engine built by the studio. Ludeon says the game looks and plays the same. The update is a beta: it can be tried on the unstable beta branch, not as a final release.

The studio's figures come from its own testing. It says 1.7 is faster at startup, loading with large mod lists, map generation, world generation and ticks per second. A stress-tested late-game colony ran 2.2x better than on 1.6, and a 1500-mod modpack went from 14 minutes to 6 minutes to load. Ludeon notes that results will vary with each player's PC and mods.

Compatibility looks broad. According to Ludeon, 1.6 savegames load on 1.7, and 1.7 saves also work if players return to 1.6. The vast majority of mods are said to run without changes from their authors. Some may appear in yellow as "potentially unsupported" simply because the version number changed. Ludeon warns that PCs more than 10 years old may not run 1.7 and asks affected players to report it on the official RimWorld development Discord.

For modders, Ludeon says Waylith allows the latest C# language features and makes complex mods easier to write without hurting performance. It also says big visual changes and complex custom effects are more accessible. Once you have tested your mod, publish a version marked as 1.7-compatible so the yellow warning goes away. Ludeon also thanked more than two dozen modders who tested ahead of the debut.

GameFromScratch, which is not an official source, says a Reddit post states Waylith is built on the Brutal Framework. The description it quotes for Brutal refers to Kitten Space Agency and a developer called Ahwoo, so the link between Brutal and Ludeon's engine rests on that Reddit post and is not confirmed in Ludeon's announcement as quoted. Check Ludeon's blog post for the official details before relying on it.