swift-diagnostics

Q: How do I install swift-diagnostics?

Run npx skills add https://github.com/johnrogers/claude-swift-engineering --skill swift-diagnostics in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/swift-diagnostics/ (personal) or .claude/skills/swift-diagnostics/ (project).

by johnrogersMobile

Use when debugging NavigationStack issues (not responding, unexpected pops, crashes), build failures (SPM resolution, "No such module", hanging builds), or memory problems (retain cycles, leaks, deinit not called). Systematic diagnostic workflows for iOS/macOS.

Installs: 162
Last 24h: —
Trending rank: —
Security: Not audited

Install

Works with every agent the skills CLI supports.

npx skills add https://github.com/johnrogers/claude-swift-engineering --skill swift-diagnostics

01
Install
Run the command in your project. The CLI asks which agents to install for.
02
Describe the task
Ask your agent for something this skill covers. It loads swift-diagnostics automatically when relevant.
03
Review the result
The agent follows the SKILL.md steps, scripts and references bundled with the skill.

SKILL.md

The instructions your agent reads when the skill is triggered.

Swift Diagnostics

Systematic debugging workflows for iOS/macOS development. These patterns help identify root causes in minutes rather than hours by following structured diagnostic approaches.

Reference Loading Guide

ALWAYS load reference files if there is even a small chance the content may be required. It's better to have the context than to miss a pattern or make a mistake.

Reference	Load When
Navigation	NavigationStack not responding, unexpected pops, deep link failures
Build Issues	SPM resolution, "No such module", dependency conflicts
Memory	Retain cycles, memory growth, deinit not called
Build Performance	Slow builds, Derived Data issues, Xcode hangs
Xcode Debugging	LLDB commands, breakpoints, view debugging

Core Workflow

Identify symptom category - Navigation, build, memory, or performance
Load the relevant reference - Each has diagnostic decision trees
Run mandatory first checks - Before changing any code
Follow the decision tree - Reach diagnosis in 2-5 minutes
Apply fix and verify - One fix at a time, test each

Key Principle

80% of "mysterious" issues stem from predictable patterns:

Navigation: Path state management or destination placement
Build: Stale caches or dependency resolution
Memory: Timer/observer leaks or closure captures
Performance: Environment problems, not code bugs

Diagnose systematically. Never guess.

Common Mistakes

Skipping mandatory first checks — Jumping straight to code changes before running diagnostics (clean build, restart simulator, restart Xcode) means you'll chase ghosts. Always start with the mandatory checks.
Changing multiple things at once — "Let me delete DerivedData AND restart simulator AND kill Xcode" means you can't isolate which fix actually worked. Change one variable at a time.
Assuming you know the cause — "NavigationStack stopped working, must be my reducer" — actually it was stale DerivedData. Diagnostic trees prevent assumptions. Follow the tree, don't guess.
Missing memory basics — Calling deinit not being called is a retain cycle, but beginners often blame architecture. Use Instruments to verify leaks before refactoring. Data, not intuition.
Not isolating the problem — Testing with your whole app complicates diagnosis. Create a minimal reproducible example with just the problematic feature. Isolation reveals root causes.

FAQ

What does the swift-diagnostics skill do?

How do I install swift-diagnostics?

Run npx skills add https://github.com/johnrogers/claude-swift-engineering --skill swift-diagnostics in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/swift-diagnostics/ (personal) or .claude/skills/swift-diagnostics/ (project).

Which AI agents can use swift-diagnostics?

Any agent that supports the open Agent Skills format (a folder with a SKILL.md file), including Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, Windsurf, Cline, OpenCode and more.

Is swift-diagnostics safe to install?

No partner security audit is available yet. Skills can run commands and scripts, so read the SKILL.md and any bundled files before installing.

Who maintains swift-diagnostics?

It is published by johnrogers in johnrogers/claude-swift-engineering. It has 162 recorded installs.