RimWorld Just Ditched Unity, and the Results Are Impressive

Image via Ludeon Studios

Published Oct 13, 2026, 1:28 PM EDT

From the moment 4-year-old Cameron first stepped out into Glimmer in Spyro 2, he knew video games were going to play a central role in the rest of his life. Though he never planned to make it the focal point of his career, Cameron spent the vast majority of his spare time growing up playing games, and following graduation from the University of Reading, he thought he’d try his hand at writing a few reviews. Six years later, Cameron has reviewed countless games, written thousands of news and feature pieces, and interviewed a wide range of developers for GameRant.

With its latest 1.7 update, RimWorld has officially switched its game engine. For the last eight years, RimWorld has been running on the Unity engine. Now it’s running on Ludeon Studios’ own in-house Waylith engine, and it seems to be thriving.

RimWorld Has Switched to the Waylith Engine

Officially announced via a new blog post on the Ludeon Studios website, RimWorld has just swapped out its Unity engine for Ludeon’s in-house Waylith engine. While RimWorld reportedly “looks and plays exactly the same” according to this latest Ludeon blog post, the new Waylith engine is said to have improved technical performance by “2–4x.” To switch over to the new engine right now, RimWorld players on PC will need to download the game’s 1.7 update via the unstable Steam branch. Save data will carry over from 1.6 to 1.7, and vice versa if players decide to switch back to using Unity.

Ludeon Studios’ blog post sheds a bit more light on what exactly has been improved with this new Waylith engine. Startup times are generally faster, load times are also faster across the board, including for map generation and world generation. Even a RimWorld game with hundreds of mods installed is said to run much more efficiently, with Ludeon’s own testing resulting in a late-game colony with 1,500 mods installed having its load time reduced from 14 minutes (running on Unity) to just 6 minutes on Waylith.

Ludeon states that performance results might vary depending on the number and type of mods installed, but over on the r/gaming subreddit it’s slowly being confirmed that most RimWorld mods are indeed still fully functional and that the game is now around 2x faster. Ludeon also warns that some older RimWorld mods may appear with a ‘potentially unsupported’ yellow tag in the game’s mod menu, but says this can be easily fixed by modders simply publishing a version update that marks the mod as 1.7-compatible.