# Swiftui Hardening

> Reproduce and harden macOS SwiftUI runtime, layout, hosting, list/table, state-restoration, stale-cache, focus, and hover failures that unit tests do not catch.

- Skill: `rcarmo/swiftui-hardening` (Agent Skill, multi-file: 3 files)
- Install (CLI): `npx skillmds@latest add rcarmo/swiftui-hardening`
- Raw SKILL.md: https://api.skillmd.com/api/skills/rcarmo/swiftui-hardening/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- License: MIT
- Author: rcarmo (https://skillmd.com/u/rcarmo)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/rcarmo/swiftui-hardening

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# SwiftUI hardening

Read `references/runtime-hardening.md`. Use for crashes, layout breakage, frozen/stale UI, hover/list defects, restoration surprises, hosting issues, or any “works in tests but fails live” report.

## Workflow

1. Reproduce on the exact macOS minor version, hardware class, window size/state, input method, and hosting context.
2. Reduce to the smallest view/state transition while preserving the failure.
3. Classify it: structural identity/transition, layout proposal/priority, observation/cache, list/table/scroll container, storage/restoration, focus/hover, or AppKit/SwiftUI hosting mismatch.
4. Replace brittle composition with the simplest system-native invariant.
5. Add a deterministic logic regression test where possible and a documented live-run scenario where not.
6. Run repeated state changes, window resize/full-screen/tile changes, navigation and modal cycles, appearance, accessibility, focus, and lowest-supported-macOS checks.
7. Record the failure mode and fix in a feature note if it is non-obvious.

## Guardrails

- A passing unit suite is not a passing app; live-run non-trivial view changes.
- Do not turn one observed framework bug into a universal rule without macOS-version and hosting evidence.
- Prefer stable view identity and dimensional/modifier changes when structural insertion/removal destabilizes hosted layouts.
- Rebuild snapshot-derived caches from the canonical source after mutations.
- Treat `@SceneStorage`/restoration defaults as persisted user state requiring migration.
- Hover-only actions must not reflow rows and need keyboard/menu alternatives.

## Output

Report the macOS/hardware/window/input matrix, minimal trigger, classification, evidence, fix, regression protection, live-run results, and uncertainty about OS-specific behaviour.