EnTT is a header-only entity component system library written in modern C++.
The entity-component-system pattern addresses the limitations of traditional object-oriented hierarchies in game development by separating data from behavior. EnTT implements this architectural pattern to enable flexible composition of game entities through components, allowing developers to build complex behaviors by combining simple, reusable pieces rather than relying on deep inheritance chains. The library is designed around data-oriented principles, organizing data for cache efficiency and enabling high-performance iteration over entities with specific component combinations.
EnTT suits projects where flexibility and performance matter equally. Game developers benefit from the ability to rapidly prototype and iterate on entity behaviors without restructuring class hierarchies. The library's header-only nature and lack of external dependencies make integration straightforward into existing projects. Beyond games, the ECS pattern applies to any system managing many objects with varying capabilities, such as simulations or real-time applications. The project has proven production-ready through adoption in major commercial products including Minecraft and ArcGIS Runtime SDKs.
The project maintains a stable codebase with careful attention to reliability and backward compatibility. Development activity shows consistent engagement with the community through multiple communication channels including a dedicated chat server and wiki documentation. The maintainers actively curate a list of projects using the library and encourage users to contribute their own. Testing infrastructure is in place to verify correctness across the codebase. The project provides integration support through multiple packaging tools and build systems, reflecting responsiveness to diverse user environments.
