# genaray/Arch

A high-performance C# based Archetype & Chunks Entity Component System (ECS) with optional multithreading.

Repository: https://github.com/genaray/Arch
Canonical: https://ross.abutalabs.com/products/arch
Homepage: https://arch-ecs.gitbook.io/arch
Language: C#
License: Apache-2.0
License Family: permissive
Topics: csharp, dotnet, ecs, entity-component-system, game, game-development, dotnet-core, netstandard21, fast, gamedev, unity, entity-framework, godot, multithreading, monogame, monogame-community, monogame-framework, stride, net8, net6
Last push: 2026-08-06T18:30:40+00:00

## Health v2 (maintenance only)
Score: 73/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 96, release rhythm 28, longevity 100
- inputs: {"age_days": 1420, "days_push": 27, "days_rel": 463, "gap_med": 75, "n_releases_24m": 2}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1808, forks 172 (observed 2026-08-28T04:05:39.217413+00:00)

## What it is
Arch is a high-performance C# Entity Component System (ECS) library based on archetypes and chunks, with optional multithreading. It targets .NET Standard 2.1 and .NET 6/8, making it usable in Unity, Godot, MonoGame, Stride, and other C# projects.

## Use cases
- entity component system for c# game development
- fast ecs library for unity or godot
- data-oriented programming in dotnet
- manage thousands of game entities efficiently
- multithreaded entity queries in c#
- cache-friendly component iteration

## When to choose
- you need a fast, minimal ECS in C# comparable to C++/Rust ECS libraries
- you develop with Unity, Godot, MonoGame, or Stride and want a modern ECS
- you want a simple, unbloated API with active maintenance and extensions

## When to avoid
- you need a full game engine rather than an ECS library
- your project is not on .NET/C#
- you prefer a batteries-included ECS with built-in rendering, networking, or editor tooling

## Facets
- artifact type: library
- maturity: active
- function: game-engine, concurrency
- domain: -
- platform: dotnet, cpp, cross-platform
- tags: ecs, entity-component-system, archetype, chunks, unity, godot, monogame, stride, csharp, multithreading, performance, game-development, gamedev, data-oriented-programming

## Member repositories
- genaray/Arch (main) score 73

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:39.217413+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:21:22.725697+00:00, confidence not recorded.
  - readme: https://github.com/genaray/Arch (fetched 2026-08-28T04:05:39.217413+00:00, sha df280ececa6a)
  - homepage: https://arch-ecs.gitbook.io/arch (fetched 2026-08-29T11:00:14.574813+00:00, sha 888feffc1cf4)
- Data as of 2026-08-30T08:39:29.467469+00:00.