Unity Ecs Patterns

When to use this skill

Use Unity Ecs Patterns when an AI agent needs a reusable SKILL.md workflow for this job: Master Unity ECS (Entity Component System) with DOTS, Jobs, and Burst for high-performance game development. Use when building data-oriented games, optimizing performance, or working with large entity counts.

When not to use it

Skip Unity Ecs Patterns when the task is outside the coding category, or when a more specific skill in this directory already covers the same workflow with clearer triggers.

How to install

1. Personal install: create ~/.claude/skills/unity-ecs-patterns/SKILL.md (and any bundled scripts) so Claude Code, Claude Desktop, and compatible agents can load it in every project.
2. Project install: commit the same folder at .claude/skills/unity-ecs-patterns/ so teammates get the skill with the repo.
3. Restart the agent session after copying files so it re-scans the skills directory, then ask for the task in words that match the skill description.

Full install guide for Claude, Cursor, and Codex

What this skill does

# Unity ECS Patterns

Production patterns for Unity's Data-Oriented Technology Stack (DOTS) including Entity Component System, Job System, and Burst Compiler.

## When to Use This Skill

- Building high-performance Unity games - Managing thousands of entities efficiently - Implementing data-oriented game systems - Optimizing CPU-bound game logic - Converting OOP game code to ECS - Using Jobs and Burst for parallelization

## Core Concepts

### 1. ECS vs OOP

| Aspect | Traditional OOP | ECS/DOTS | | ----------- | ----------------- | --------------- | | Data layout | Object-oriented | Data-oriented | | Memory | Scattered | Contiguous | | Processing | Per-object | Batched | | Scaling | Poor with count | Linear scaling | | Best for | Complex behaviors | Mass simulation |

### 2. DOTS Components

``` Entity: Lightweight ID (no data) Component: Pure data (no behavior) System: Logic that processes components World: Container for entities Archetype: Unique combination of components Chunk: Memory block for same-archetype entities ```

## Detailed patterns and worked examples

Detailed pattern documentation lives in `references/details.md`. Read that file when the navigation tier above is insufficient.

## Best Practices

### Do's

- **Use ISystem over SystemBase** - Better performance - **Burst compile everything** - Massive speedup - **Batch structural changes** - Use ECB - **Profile with Profiler** - Identify bottlenecks - **Use Aspects** - Clean component grouping

### Don'ts

- **Don't use managed types** - Breaks Burst - **Don't structural change in jobs** - Use ECB - **Don't over-architect** - Start simple - **Don't ignore chunk utilization** - Group similar entities - **Don't forget disposal** - Native collections leak

Intended uses

• Building high-performance Unity games
• Managing thousands of entities efficiently
• Implementing data-oriented game systems
• Optimizing CPU-bound game logic
• Converting OOP game code to ECS
• Using Jobs and Burst for parallelization