Axiom Build Performance

What it does

This skill, Axiom Build Performance, provides systematic analysis and optimization of Xcode build performance. It focuses on measuring build times before attempting optimizations, prioritizing improvements to the critical path. The skill helps identify slow-compiling Swift code and optimize CI/CD build pipelines by analyzing the three phases of the build process: scan, modules, and compile. A quick-start command /axiom:optimize-build is available for automated scanning and immediate fixes.

When to use it

• Build times have significantly increased.
• Incremental builds are taking too long.
• You need to analyze the Xcode Build Timeline.
• You want to identify slow-compiling Swift code.
• You're optimizing CI/CD build times.
• You’re investigating a build performance regression.

Key capabilities

• Baseline Measurement: Provides instructions for measuring initial build times (clean and incremental builds) and identifying the longest phase (compile, link, or scripts).
• Build Timeline Analysis (Xcode 14+): Guides users on how to interpret Xcode's Build Timeline to identify critical paths and bottlenecks.
• Critical Path Identification: Explains the concept of the critical path as the limiting factor in build speed.
• Bottleneck Diagnosis: Offers a decision tree to guide analysis based on whether compilation or linking is the primary bottleneck.
• Automated Optimization (Quick Win): The /axiom:optimize-build command provides automated scanning for common issues and immediate fixes.

Example prompts

• /axiom:optimize-build - To run an automated build performance scan.
• "Analyze my Xcode build timeline." - To initiate a build timeline analysis.
• "How do I measure the baseline build time?" - To get instructions on performing initial build measurements.

Tips & gotchas

• Baseline is Required: Always perform a clean build and measure baseline times before attempting any optimizations to ensure changes are truly beneficial.
• Xcode Version Requirement: The Build Timeline analysis feature requires Xcode 14 or later.
• Focus on the Critical Path: Prioritize optimizing tasks along the critical path, as these have the greatest impact on overall build time.