Build Debugging

Guidance for build failures caused by dependencies and build configuration rather than code. The skill helps your assistant tell package, framework and project settings problems apart before choosing a fix.

When to Use

Use this skill when:

• A newly added package produces a "No such module" error
• A build fails because multiple commands produce the same output file
• CocoaPods installs successfully but the project still fails to build
• Package resolution hangs, or dependencies require conflicting versions
• A build works locally but fails in CI, or builds in Debug but fails in Release
• Xcode 27 ignores -ld_classic, or dependency scanning reports duplicate Clang module names

Example Prompts

• "I added a Swift package and now the compiler cannot find its module."
• "Why do two targets produce the same file?"
• "My build log says '-ld_classic is no longer supported and will be ignored' — does that matter?"
• "The build failed but the error scrolled away. Can you find it without rebuilding?"

What This Skill Provides

• Checks for missing modules, framework search paths and duplicate target membership
• CocoaPods lockfile and installation diagnostics, including opening the workspace rather than the project
• SPM version conflicts, dependency graphs and package cache resets
• Dependency strategies: exact versions, version ranges, forks and excluded transitive dependencies
• Debug and Release build setting comparisons
• Xcode 27 linker and dependency-scanning guidance
• A short diagnosis to run before trying a quick fix suggested under deadline pressure
• Build and test output saved through axbuild, or a plain log file where axbuild isn't available

Documentation Scope

This page documents the build-debugging skill (in the axiom-build suite), which your assistant loads when a build fails because of dependencies, packages or build settings rather than code. When your assistant runs a build or test, the skill has it use axbuild where available: axbuild returns a short summary and saves the full report and compiler log, so your assistant can find the real error without rebuilding. To hand the whole diagnosis to an agent, run /axiom:fix-build, which launches the build-fixer agent; it asks before deleting caches or stopping processes. For package conflicts specifically, /axiom:resolve-deps launches the spm-conflict-resolver agent.

Related

• xcode-debugging – Environment checks for Xcode and simulator problems, which come before dependency checks
• build-fixer – Autonomous diagnosis using retained build evidence
• spm-conflict-resolver – Explains SPM version conflicts, "No such module" errors and duplicate symbols
• build-performance – For builds that succeed but take too long
• swift-concurrency – Swift 6 isolation and concurrency build errors
• Tools – axbuild installation, report handling and compatibility limits