#ecs #derive #macro #entity-component #entity

macro shard_ecs_derive

Contains derive macros for the Shard Entity Component System

1 unstable release

0.1.0 Jan 31, 2022

Used in shard-ecs

MIT license



Shard is an Archetype-based Entity Component System implemented in Rust.


  • Systems are (currently) implicit.
  • Supports #![no_std] environments. (Requires alloc however)
  • Up to 14 components per entity.
  • Up to 65K archetypes.
  • Up to 16.7 million entities.
  • Dependency free.
  • (Mostly) unit tested.


See the examples directory for details, but in short:

  1. Implement Component trait for types which you wish to use as components.
  2. Create a Registry.
  3. Use the Registry to construct entities.
  4. Add or remove components from entities.
  5. Iterate over entities matching certain subsets of components.


  • Query support
  • Filter iterators => done as of 0.2.3.
  • Procedural derive macro for Components. => done as of 0.2.6.
  • Allow replacing components.
  • Allow adding/removing multiple components at once.
  • Faster archetype lookups (using a graph).
  • Component dependencies/exclusions.


~30K SLoC