RimWorld and Ahwoo unveiled the game development framework BRUTAL on October 15, 2026. This framework allows developers to combine technical libraries according to project needs, and can be used directly for game production or as a technical foundation for studios building their own indie game engines.
RimWorld is led by Dean Hall, the developer of DayZ. BRUTAL is built on C# and .NET, combined with C++ libraries and lower-level graphics features such as Vulkan. Unlike mature engines like Unity and Unreal Engine that provide complete feature suites, it does not come with a full set of editors and production tools; developers need to select, adjust, and maintain the underlying systems themselves.
BRUTAL is already being used for Kitten Space Agency, a space flight simulation game currently in development by the RimWorld team, and has also supported Ludeon Studios' migration of their colony management game RimWorld to the independent Waylith engine. Tests conducted by Ludeon Studios showed that performance improved two to four times compared to the Unity version, but these results come from the studio's own projects and should not be considered universally reproducible across all projects.
Regarding licensing, BRUTAL can be used for commercial games without requiring developers to pay royalties, but they must still comply with conditions such as attribution and displaying the logo before the game starts. Due to the lack of complete tools associated with mature commercial engines, teams adopting this framework need to possess corresponding programming capabilities and bear the costs of development and long-term maintenance. Therefore, its positioning is more suited for teams that wish to control their technology stack and have a genuine need for self-developed infrastructure.