Everywhere Cachet looks
Cachet only looks in places it knows: 22 of them, each with what it is, what happens if you remove it, and when it comes back. These are the rules the app uses, in its own words.
Developer
Xcode build data and device support.
- DerivedData~/Library/Developer/Xcode/DerivedDataOn next buildHigh
- iOS DeviceSupport~/Library/Developer/Xcode/iOS DeviceSupportWhen a device connectsHigh
- watchOS DeviceSupport~/Library/Developer/Xcode/watchOS DeviceSupportWhen a watch connectsHigh
- Previews~/Library/Developer/Xcode/UserData/PreviewsOn next previewMedium
- Simulator caches~/Library/Developer/CoreSimulator/CachesAutomaticallyHigh
- Archives~/Library/Developer/Xcode/ArchivesNeverReview
Package caches
Downloaded packages for npm, Swift, Homebrew and others.
- npm cache~/.npm/_cacacheOn next installHigh
- Yarn cache~/Library/Caches/YarnOn next installHigh
- pip cache~/Library/Caches/pipOn next installHigh
- Homebrew downloads~/Library/Caches/HomebrewOn next installHigh
- Swift packages~/Library/Caches/org.swift.swiftpmOn next resolveHigh
- CocoaPods cache~/Library/Caches/CocoaPodsOn next installHigh
- Go build cache~/Library/Caches/go-buildOn next buildHigh
- Playwright browsers~/Library/Caches/ms-playwrightOn next test runMedium
- Playwright browsers (MCP)~/Library/Caches/ms-playwright-mcpOn next runMedium
- Gradle caches~/.gradle/cachesOn next buildMedium
App caches
Temporary files apps rebuild as you use them.
Old installers
Installers in Downloads that haven’t changed in 90 days.
Logs
Log files apps write while they run.
Simulators
One Terminal command removes devices that can’t run any more.
What the confidence means
- High
- It rebuilds itself when needed, such as a cache or build data.
- Medium
- Usually safe, but something lowers Cachet’s confidence, such as its app being open or it changing today.
- Review
- It won’t come back once removed, so Cachet asks you to look first.
Each place starts at the level shown. What Cachet sees on your Mac can lower it, never raise it.