RimWorld Switches Engine From Unity To The Devs' Own, Faster Waylith Engine, All Apparently Without Breaking Mods Somehow

Ludeon Studios, the development team behind the popular sci-fi colony simulator RimWorld, has shared details regarding a massive technical overhaul coming in the game's upcoming 1.7 update. According to a recent news post published on Steam, the studio is abandoning the Unity engine to transition the title onto its own proprietary software, dubbed the Waylith Engine. Despite the foundational change to how the game is powered, the creators assure players that the core presentation and gameplay feel will remain entirely identical.

The primary motivation for building and deploying this custom engine lies in substantial performance gains. Ludeon Studios claims that general game efficiency will rise by roughly two to four times compared to previous builds. The engineering upgrade promises to accelerate startup sequences, map creation, world generation, and overall ticks-per-second processing speed. To illustrate the speed increase, the developers noted that an extensive setup containing 1,500 player-made modifications had its boot time reduced from 14 minutes down to just 6 minutes.

Perhaps the most remarkable aspect of this architectural shift is its seamless compatibility with the game's massive library of community modifications. Typically, transitioning a video game to an entirely different engine breaks existing add-ons and requires creators to rewrite their code. However, Ludeon Studios stated that players' current modifications should continue to function normally. While certain mods might trigger a harmless warning label stating they are potentially unsupported due to the version increment, their actual functionality is expected to remain intact.

In addition to preserving community content, the upcoming patch ensures that existing player progression will remain safe. Colony saves created in version 1.6 can be freely loaded into version 1.7 without data loss, eliminating the need for players to abandon their ongoing colonies. For those eager to evaluate the technical claims early, Ludeon Studios has made the 1.7 update available for public testing via the beta branch features on Steam, allowing both casual users and mod authors to test their current setups.

Early feedback gathered from community discussions on Reddit indicates that the update is largely delivering on its promises. Players testing the beta build have reported noticeable performance boosts alongside functioning mod loads. However, the testing phase has also revealed a few trade-offs, with some users highlighting a marked increase in system memory utilization. Additionally, Ludeon Studios cautioned that hardware exceeding ten years of age might struggle or fail to run version 1.7 altogether, meaning a segment of the audience with older computer setups may need to upgrade.

This bold move away from commercial engine architecture echoes previous high-profile shifts within the independent development space. A few years prior, the creators of Slay the Spire 2 abandoned Unity in favor of the open-source Godot engine following controversial policy changes regarding per-install developer fees. By establishing its own tailor-made Waylith Engine, Ludeon Studios secures complete technical independence from third-party engine creators while dramatically enhancing the capability of its simulation software.