Enable compilation caching and eager linking for faster builds#2808
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AvdLee wants to merge 1 commit intokickstarter:mainfrom
Open
Enable compilation caching and eager linking for faster builds#2808AvdLee wants to merge 1 commit intokickstarter:mainfrom
AvdLee wants to merge 1 commit intokickstarter:mainfrom
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Enable recommended Xcode build settings to improve build performance: - COMPILATION_CACHING = YES (Debug + Release): caches compilation results so repeated builds of unchanged sources are served from cache. Benefits branch switching, pulling changes, and CI builds. - EAGER_LINKING = YES (Debug): allows the linker to start before all compilation tasks finish, reducing wall-clock build time. Benchmark (Xcode 26.2, Apple Silicon, 1,991 Swift files): - Clean build: 83.4s → 83.5s (within noise) - Cached clean: 83.1s (warm compilation cache) - Zero-change: 10.9s → 10.6s The compilation cache benefit is most significant during real developer workflows (branch switching, incremental builds after pulling) rather than clean-build benchmarks where the cache starts cold each run.
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Summary
This PR enables recommended Xcode build settings to improve build performance for the Kickstarter iOS app.
Changes
COMPILATION_CACHING = YES(Debug + Release): Caches compilation results so repeated builds of unchanged sources are served from cache. The biggest wins come from branch switching, pulling changes, and CI builds where many files remain unchanged between builds.EAGER_LINKING = YES(Debug): Allows the linker to start work before all compilation tasks finish, reducing wall-clock build time during development.Benchmark (Xcode 26.2, Apple Silicon, 1,991 Swift files)
Clean build times are within noise (the cache population overhead matches the cache benefit in a cold-cache benchmark). The real benefit manifests during developer workflows where the cache persists: branch switching, incremental builds after pulling, and CI with persistent DerivedData.
How these were found
Analysis was performed using Xcode Build Optimization Agent Skills, which benchmarks builds, audits project settings against best practices, and identifies optimization opportunities.
Side note
While setting up the OSS build, I noticed
Secrets.Statsigis referenced inAppDelegate.swiftbut not stubbed inConfigs/Secrets.swift.example. This causes a compile error for open-source contributors. You may want to add a stub to the example file.Test plan
xcodebuild -showBuildSettings