Aztecs

A type-safe and friendly ECS for Haskell.

Features

• High-performance: Components are stored by their unique sets in vector-based archetypes
• Dynamic components: Scripts and remote interfaces can create unique components with runtime-specified components
• Type-safe DSL: Components and systems are accessed by marker types that determine their storage
• Modular design: Aztecs can be extended for a variety of use cases

import Control.Arrow
import Data.Aztecs
import qualified Data.Aztecs.Access as A
import qualified Data.Aztecs.System as S
import qualified Data.Aztecs.World as W

newtype Position = Position Int deriving (Show)

instance Component Position

newtype Velocity = Velocity Int deriving (Show)

instance Component Velocity

data Setup

instance System IO Setup where
  task = S.queue (A.spawn_ (Position 0 :& Velocity 1))

data Movement

instance System IO Movement where
  task = S.map (\(Position x :& Velocity v) -> Position (x + v)) >>> S.run print

main :: IO ()
main = do
  w <- S.runSystem @_ @Setup W.empty
  _ <- S.runSystem @_ @Movement w
  return ()

Benchmarks

Aztecs is currently faster than bevy-ecs, a popular and high-performance ECS written in Rust, for simple mutating queries.

Inspiration

Aztecs' approach to type-safety is inspired by Bevy, but with direct archetype-based storage similar to Flecs.