/axiom-build
Use when ANY iOS build fails, test crashes, Xcode misbehaves, or environment issue occurs before debugging code. Covers build failures, compilation errors, dependency conflicts, simulator problems, environment-first diagnostics.
$ npx -y skills add charleswiltgen/axiom --skill axiom-build --agent claude-codeHow it fires
How this skill gets triggered: by you, by Claude, or both.
- Fires itselfAuto-invocation. Claude auto-loads it when your prompt matches the work.Auto-invocation is when the right skill fires by itself at the right moment, driven by a FLOW.md router and a hook, instead of you invoking it by name. It is the difference between a skill being installed and a skill actually getting used.Read the full definition →
- You can call itInvoke it directly when you want it.
- Slash command
/axiom-build
Context preview
The summary Claude sees to decide when to auto-load this skill.
Use when ANY iOS build fails, test crashes, Xcode misbehaves, or environment issue occurs before debugging code. Covers build failures, compilation errors, dependency conflicts, simulator problems, environment-first diagnostics.
SKILL.md
axiom-build.SKILL.mdname: axiom-build
description: Use when ANY iOS build fails, test crashes, Xcode misbehaves, or environment issue occurs before debugging code. Covers build failures, compilation errors, dependency conflicts, simulator problems, environment-first diagnostics.
license: MIT
Build & Environment
**You MUST use this skill for ANY build, environment, or Xcode-related issue before debugging application code.**
<!-- AXIOM_AUDITOR_INLINE_BEGIN — auto-maintained by scripts/build-inlined-auditors.ts; do not hand-edit --> > **Not on Claude Code?** Where this router says "Launch `some-auditor` agent", read that auditor's file in this suite and follow it inline — the same procedure, needing only file search and read. > > Available here: `skills/modernization-helper.md`. > Homed in another suite: `axiom-security/skills/security-privacy-scanner.md`. > > Agents that need Bash — builds, tests, simulators, crash symbolication — stay Claude Code-only; there is no inline equivalent for those. <!-- AXIOM_AUDITOR_INLINE_END -->
When to Use
Use this router when you encounter:
- Build failures (`BUILD FAILED`, compilation errors, linker errors)
- Test crashes or hangs
- Simulator issues (won't boot, device errors)
- Xcode misbehavior (stale builds, zombie processes)
- Dependency conflicts (CocoaPods, SPM)
- Build performance issues (slow compilation)
- Environment issues before debugging code
Routing Logic
This router invokes specialized skills based on the specific issue:
1. Environment-First Issues → **xcode-debugging**
**Triggers**:
- `BUILD FAILED` without obvious code cause
- Tests crash in clean project
- Simulator hangs or won't boot
- "No such module" after SPM changes
- Zombie `xcodebuild` processes
- Stale builds (old code still running)
- Clean build differs from incremental build
- Device Hub / predicted-vs-built issues in Xcode 27 (`OS27`)
- Reproducing a device-only bug on a simulator (Device Hub) (`OS27`)
**Why xcode-debugging first**: 90% of mysterious issues are environment, not code. Check this BEFORE debugging code.
**Invoke**: `skills/xcode-debugging.md`
---
2. Slow Builds → **build-performance**
**Triggers**:
- Compilation takes too long
- Type checking bottlenecks
- Want to optimize build time
- Build Timeline shows slow phases
**Invoke**: `skills/build-performance.md`
---
3. SPM Dependency Conflicts → **spm-conflict-resolver** (Agent)
**Triggers**:
- SPM resolution failures
- "No such module" after adding package
- Duplicate symbol linker errors
- Version conflicts between packages
- Swift 6 package compatibility issues
- Package.swift / Package.resolved conflicts
**Why spm-conflict-resolver**: Specialized agent that analyzes Package.swift and Package.resolved to diagnose and resolve Swift Package Manager conflicts.
**Invoke**: Launch `spm-conflict-resolver` agent
---
4. Security & Privacy Audit → **security-privacy-scanner** (Agent)
**Triggers**:
- App Store submission prep
- Privacy Manifest requirements (iOS 17+)
- Hardcoded credentials in code
- Sensitive data storage concerns
- ATS violations
- Required Reason API declarations
**Why security-privacy-scanner**: Specialized agent that scans for security vulnerabilities and privacy compliance issues.
**Invoke**: Launch `security-privacy-scanner` agent or `/axiom:audit security`
---
5. iOS 17→18 Modernization → **modernization-helper** (Agent)
**Triggers**:
- Migrate ObservableObject to @Observable
- Update @StateObject to @State
- Adopt modern SwiftUI patterns
- Deprecated API cleanup
- iOS 17+ migration
**Why modernization-helper**: Specialized agent that scans for legacy patterns and provides migration paths with code examples.
**Invoke**: Launch `modernization-helper` agent or `/axiom:audit modernization`
---
6. Build Failure Auto-Fix → **build-fixer** (Agent)
**Triggers**:
- BUILD FAILED with no clear error details
- Build sometimes succeeds, sometimes fails
- App builds but runs old code
- "Unable to boot simulator" error
- Want automated environment-first diagnostics
**Why build-fixer**: Autonomous agent that checks zombie processes, Derived Data, SPM cache, and simulator state before investigating code. Saves 30+ minutes on environment issues.
**Invoke**: Launch `build-fixer` agent or `/axiom:fix-build`
---
7. Slow Build Optimization → **build-optimizer** (Agent)
**Triggers**:
- Builds take too long
- Want to identify slow type checking
- Expensive build phase scripts
- Suboptimal build settings
- Want parallelization opportunities
**Why build-optimizer**: Scans Xcode projects for build performance optimizations — slow type checking, expensive scripts, suboptimal settings — to reduce build times by 30-50%.
**Invoke**: Launch `build-optimizer` agent or `/axiom:optimize-build`
---
8. General Dependency Issues → **build-debugging**
**Triggers**:
- CocoaPods resolution failures
- "Multiple commands produce" errors
- Framework version mismatches
- Non-SPM dependency graph conflicts
**Invoke**: `skills/build-debugging.md`
---
9. TestFlight Crash Triage → **testflight-triage**
**Triggers**:
- Beta tester reported a crash
- Crash reports in Xcode Organizer
- Crash logs aren't symbolicated
- TestFlight feedback with screenshots
- App was killed but no crash report
**Why testflight-triage**: Systematic workflow for investigating TestFlight crashes and reviewing beta feedback. Covers symbolication, crash interpretation, common patterns, and Claude-assisted analysis.
**Invoke**: See axiom-shipping (skills/testflight-triage.md)
---
10. App Store Connect Navigation → **app-store-connect-ref**
**Triggers**:
- How to find crashes in App Store Connect
- ASC metrics dashboard navigation
- Understanding crash-free users percentage
- Comparing crash rates between versions
- Exporting crash data from ASC
- App Store Connect API for crash data
**Why app-store-connect-ref**: Reference for navigating ASC crash analysis, metrics dashboards, and data export w
Read more
name: axiom-build description: Use when ANY iOS build fails, test crashes, Xcode misbehaves, or environment issue occurs before debugging code. Covers build failures, compilation errors, dependency conflicts, simulator problems, environment-first diagnostics. license: MIT
Build & Environment
**You MUST use this skill for ANY build, environment, or Xcode-related issue before debugging application code.**
<!-- AXIOM_AUDITOR_INLINE_BEGIN — auto-maintained by scripts/build-inlined-auditors.ts; do not hand-edit --> > **Not on Claude Code?** Where this router says "Launch `some-auditor` agent", read that auditor's file in this suite and follow it inline — the same procedure, needing only file search and read. > > Available here: `skills/modernization-helper.md`. > Homed in another suite: `axiom-security/skills/security-privacy-scanner.md`. > > Agents that need Bash — builds, tests, simulators, crash symbolication — stay Claude Code-only; there is no inline equivalent for those. <!-- AXIOM_AUDITOR_INLINE_END -->
When to Use
Use this router when you encounter:
- Build failures (`BUILD FAILED`, compilation errors, linker errors)
- Test crashes or hangs
- Simulator issues (won't boot, device errors)
- Xcode misbehavior (stale builds, zombie processes)
- Dependency conflicts (CocoaPods, SPM)
- Build performance issues (slow compilation)
- Environment issues before debugging code
Routing Logic
This router invokes specialized skills based on the specific issue:
1. Environment-First Issues → **xcode-debugging**
**Triggers**:
- `BUILD FAILED` without obvious code cause
- Tests crash in clean project
- Simulator hangs or won't boot
- "No such module" after SPM changes
- Zombie `xcodebuild` processes
- Stale builds (old code still running)
- Clean build differs from incremental build
- Device Hub / predicted-vs-built issues in Xcode 27 (`OS27`)
- Reproducing a device-only bug on a simulator (Device Hub) (`OS27`)
**Why xcode-debugging first**: 90% of mysterious issues are environment, not code. Check this BEFORE debugging code.
**Invoke**: `skills/xcode-debugging.md`
---
2. Slow Builds → **build-performance**
**Triggers**:
- Compilation takes too long
- Type checking bottlenecks
- Want to optimize build time
- Build Timeline shows slow phases
**Invoke**: `skills/build-performance.md`
---
3. SPM Dependency Conflicts → **spm-conflict-resolver** (Agent)
**Triggers**:
- SPM resolution failures
- "No such module" after adding package
- Duplicate symbol linker errors
- Version conflicts between packages
- Swift 6 package compatibility issues
- Package.swift / Package.resolved conflicts
**Why spm-conflict-resolver**: Specialized agent that analyzes Package.swift and Package.resolved to diagnose and resolve Swift Package Manager conflicts.
**Invoke**: Launch `spm-conflict-resolver` agent
---
4. Security & Privacy Audit → **security-privacy-scanner** (Agent)
**Triggers**:
- App Store submission prep
- Privacy Manifest requirements (iOS 17+)
- Hardcoded credentials in code
- Sensitive data storage concerns
- ATS violations
- Required Reason API declarations
**Why security-privacy-scanner**: Specialized agent that scans for security vulnerabilities and privacy compliance issues.
**Invoke**: Launch `security-privacy-scanner` agent or `/axiom:audit security`
---
5. iOS 17→18 Modernization → **modernization-helper** (Agent)
**Triggers**:
- Migrate ObservableObject to @Observable
- Update @StateObject to @State
- Adopt modern SwiftUI patterns
- Deprecated API cleanup
- iOS 17+ migration
**Why modernization-helper**: Specialized agent that scans for legacy patterns and provides migration paths with code examples.
**Invoke**: Launch `modernization-helper` agent or `/axiom:audit modernization`
---
6. Build Failure Auto-Fix → **build-fixer** (Agent)
**Triggers**:
- BUILD FAILED with no clear error details
- Build sometimes succeeds, sometimes fails
- App builds but runs old code
- "Unable to boot simulator" error
- Want automated environment-first diagnostics
**Why build-fixer**: Autonomous agent that checks zombie processes, Derived Data, SPM cache, and simulator state before investigating code. Saves 30+ minutes on environment issues.
**Invoke**: Launch `build-fixer` agent or `/axiom:fix-build`
---
7. Slow Build Optimization → **build-optimizer** (Agent)
**Triggers**:
- Builds take too long
- Want to identify slow type checking
- Expensive build phase scripts
- Suboptimal build settings
- Want parallelization opportunities
**Why build-optimizer**: Scans Xcode projects for build performance optimizations — slow type checking, expensive scripts, suboptimal settings — to reduce build times by 30-50%.
**Invoke**: Launch `build-optimizer` agent or `/axiom:optimize-build`
---
8. General Dependency Issues → **build-debugging**
**Triggers**:
- CocoaPods resolution failures
- "Multiple commands produce" errors
- Framework version mismatches
- Non-SPM dependency graph conflicts
**Invoke**: `skills/build-debugging.md`
---
9. TestFlight Crash Triage → **testflight-triage**
**Triggers**:
- Beta tester reported a crash
- Crash reports in Xcode Organizer
- Crash logs aren't symbolicated
- TestFlight feedback with screenshots
- App was killed but no crash report
**Why testflight-triage**: Systematic workflow for investigating TestFlight crashes and reviewing beta feedback. Covers symbolication, crash interpretation, common patterns, and Claude-assisted analysis.
**Invoke**: See axiom-shipping (skills/testflight-triage.md)
---
10. App Store Connect Navigation → **app-store-connect-ref**
**Triggers**:
- How to find crashes in App Store Connect
- ASC metrics dashboard navigation
- Understanding crash-free users percentage
- Comparing crash rates between versions
- Exporting crash data from ASC
- App Store Connect API for crash data
**Why app-store-connect-ref**: Reference for navigating ASC crash analysis, metrics dashboards, and data export w
Battle-tested skills, agents, and tools for modern Apple OS development — Swift 6, SwiftUI, Liquid Glass, Apple Intelligence, and more. Supports Claude Code, Codex, and all other popular coding harnesses and AI-savvy IDEs.
Repo: charleswiltgen/axiom
Other skills on axiom.
- /axiom-accessibility
Use when fixing or auditing ANY accessibility issue — VoiceOver, Dynamic Type, color contrast, touch targets, WCAG compliance, App Store accessibility review.
Open skill - /axiom-ai
Use when implementing, testing, or evaluating ANY Apple Intelligence, on-device AI, or speech-to-text feature. Covers Foundation Models, @Generable, LanguageModelSession, Tool protocol, eval suites, model-as-judge scoring, SpeechTranscriber, CoreML.
Open skill - /axiom-analyze-crash
Use when the user has a crash log (.
Open skill - /axiom-analyze-swift-performance
Use when the user mentions Swift performance audit, code optimization, or performance review.
Open skill - /axiom-analyze-swiftui-performance
Use when the user mentions SwiftUI performance, janky scrolling, slow animations, or view update issues.
Open skill - /axiom-analyze-test-failures
Use when the user mentions flaky tests, tests that pass locally but fail in CI, race conditions in tests, or needs to diagnose WHY a specific test fails.
Open skill

