jz315/skyecs

SkyECS, also called Sky ECS, is a Rust programming library that implements an Entity Component System, a pattern commonly used in game engines to organize game objects and their behavior. Instead of building game objects as classes with fixed properties, an ECS stores each piece of data, like position or velocity, in its own list, and systems process those lists directly. This design tends to run faster than traditional object-oriented approaches, especially with large numbers of objects, because it lets the computer process similar data together efficiently. Sky ECS is also the built-in ECS used inside a separate project by the same author called SkyEngine, a game engine. The README highlights four main design goals: very fast execution through what it calls an Archetype architecture with deep internal optimizations, built-in multithreading so it can use all the cores on a modern CPU, an API designed to be intuitive so developers can focus on their actual game logic rather than fighting the library, and a dynamic API alongside the typed one that supports runtime reflection, meant for integrating with other languages like C# or scripting languages. Using it looks like creating a World, spawning batches of entities each carrying components such as Position and Velocity structs, then running queries that loop over matching entities and update their values every frame. For larger numbers of entities, the library offers parallel versions of its iteration functions to spread the work across CPU cores automatically. The README includes a benchmark comparison table against several other well known Rust ECS libraries, including hecs, Bevy's ECS, Flecs, freecs, and Shipyard, across a few different workloads like inserting entities in bulk and iterating over prepared queries at different entity counts, with timing results in microseconds for each library. It notes the benchmark methodology and full workload list live in a separate benchmarks document, and that a newer gameplay-based benchmark trace is still pending publication. The project requires Rust 1.85 or newer and is licensed under MIT.