# Swift Memory Management

> Standards for ARC, Weak/Unowned References, and Capture Lists

- Skill: `fierzone/swift-memory-management` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add fierzone/swift-memory-management`
- Raw SKILL.md: https://api.skillmd.com/api/skills/fierzone/swift-memory-management/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: fierzone (https://skillmd.com/u/fierzone)
- Updated: 2026-09-10
- Page: https://skillmd.com/skills/fierzone/swift-memory-management

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# Swift Memory Management

## **Priority: P0**

## Implementation Guidelines

### ARC Fundamentals

- **Default**: Strong references. Swift automatically manages retain/release.
- **Weak**: Use `weak` for delegate patterns and parent-child relationships.
- **Unowned**: Use `unowned` only when reference guaranteed to outlive (rare).

### Capture Lists

- **Closures**: Always use `[weak self]` or `[unowned self]` in escaping closures.
- **Self in Structs**: No capture list needed (`self` is copied by value).
- **Multiple Captures**: `[weak self, weak delegate]`.

### Retain Cycles

- **Delegates**: Always `weak var delegate`.
- **Closures as Properties**: Use `weak` or `unowned` in capture list.
- **two-way References**: One side must be `weak`.

## Anti-Patterns

- **Strong Delegates**: `**No strong var delegate**: Use weak.`
- **Missing Capture List**: `**No self in escaping closures**: Use [weak self].`
- **Unowned Misuse**: `**Avoid unowned**: Use weak unless certain.`

## References

- [Capture Lists & Retain Cycles](references/implementation.md)