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Generated data

Generated data

Section titled “Generated data”

DerivedData

Section titled “DerivedData”

DerivedData contains build products, indexes, logs, macro/plugin products, and package checkouts. It is regenerable, but rebuilding can be expensive.

Strong candidates:

  • The recorded WorkspacePath no longer exists
  • The folder contains only package downloads and no build products
  • A project-local DerivedData folder belongs to completed work
  • The user explicitly accepts rebuilding and reindexing

Protect:

  • Active workspaces and builds
  • Custom DerivedData whose owner is unknown

Xcode may use a custom path from Settings → Locations. Do not assume every DerivedData directory is below the default home directory.

Project .build

Section titled “Project .build”

SwiftPM and project scripts frequently place large generated folders beside source. Scan only roots the user authorizes. Exclude dependency checkouts to avoid counting nested builds multiple times.

Prefer supported scoped commands when available:

Terminal window
swift package clean
swift package reset

Check swift package --help against the selected toolchain before recommending a command. Never delete Package.resolved, mirrors, registries, security configuration, or credentials.

Out of scope: shared compiler and SwiftPM caches

Section titled “Out of scope: shared compiler and SwiftPM caches”

Shared compiler caches (ModuleCache.noindex, precompiled SDK modules) and the global SwiftPM download cache (~/Library/Caches/org.swift.swiftpm) are not cleanup candidates. On an active development machine they are always needed, regenerate into the same space within days, and clearing them slows every subsequent build. Do not report or propose them.

CocoaPods cache

Section titled “CocoaPods cache”

~/Library/Caches/CocoaPods stores pod downloads that pod install re-fetches on demand. It is regenerable and safe to Trash. Project Pods/ directories are part of the working tree and are never cleanup candidates.

Documentation

Section titled “Documentation”

Downloaded documentation is usually recoverable, but manually imported DocSets may be unique. Only classify versioned Xcode cache folders as regenerable when a newer sibling exists. Never remove documentation from inside an Xcode application.

Cost language

Section titled “Cost language”

Avoid saying “safe to delete” without qualification. State the practical cost:

  • Full rebuild/reindex
  • Package or binary artifact downloads
  • Loss of offline documentation
  • Temporary failures for concurrent builds