Ludeon Studios has moved RimWorld from Unity to its own Waylith Engine in update 1.7, which is available now through Steam’s unstable beta branch. The main branch remains on version 1.6 while the studio gathers test feedback.
Ludeon says RimWorld looks and plays the same after the engine swap, but its tests showed performance improving by two to four times. One late-game stress test delivered 2.2 times better performance, while a 1,500-mod setup loaded in six minutes instead of 14. The studio cautions that results will vary by PC and mod list.
Save files work in both directions between versions 1.6 and 1.7. Ludeon says the vast majority of mods should work without changes, although some may show a compatibility warning until their creators mark them for 1.7. PCs more than about 10 years old may not run the update.
Waylith also gives modders access to newer C# features and makes complex visual effects more accessible. Ludeon says it is developing another, still-unannounced game on the engine.