Developer Data

Android The ~/Library/Android folder usually stores user-level data for Android-related tools such as Android Studio, SDK helpers, or file transfer utilities. ~/Library/Android

Devices Simulator Data Stores Xcode iOS, watchOS, and tvOS simulator device data, including app installs, settings, and test state for local development. ~/Library/Developer/CoreSimulator/Devices

Npm The ~/.npm folder stores npm cache and package data used by Node.js development tools and command-line installs. ~/.npm

Rustup The ~/.rustup folder stores Rust toolchains, components, and metadata installed by rustup for Rust development on your Mac. ~/.rustup

Virtual Machines Localized The ~/Virtual Machines.localized folder is commonly used to store virtual machine bundles and related files for virtualization apps on macOS. ~/Virtual Machines.localized

Node Modules The ~/node_modules folder usually contains JavaScript packages installed for Node.js projects and local development tools. ~/node_modules

Ruby Gems 2.6.0 This folder stores Ruby gems for the system-provided Ruby 2.6 environment and may be used by developer tools, scripts, or older macOS components. /Library/Ruby/Gems/2.6.0

Developer /Library/Developer is a shared macOS folder typically used by Apple developer tools such as Xcode for SDKs, simulators, and related resources. /Library/Developer

Xcode Junk Documentation Cache This Xcode folder stores downloaded documentation and indexing data used to browse Apple developer docs inside Xcode. Xcode Junk · ~/Library/Developer/Xcode/DocumentationCache

Xcode Junk Derived Data Xcode DerivedData stores temporary build products, indexes, and intermediate files created while building and debugging projects in Xcode. Xcode Junk · ~/Library/Developer/Xcode/DerivedData

Xcode Junk Archives Stores archived Xcode build outputs, usually created when you archive apps for distribution, testing, or keeping release snapshots. Xcode Junk · ~/Library/Developer/Xcode/Archives

Xcode Junk iOS Device Support Xcode iOS DeviceSupport stores files Xcode uses to work with specific iPhone and iPad iOS versions during development and device debugging. Xcode Junk · ~/Library/Developer/Xcode/iOS DeviceSupport

Xcode Junk Simulator Runtimes This folder stores Xcode CoreSimulator data such as simulator runtimes, devices, and related files used for iOS, watchOS, and tvOS development. Xcode Junk · ~/Library/Developer/CoreSimulator

Opt /opt is a standard Unix-style folder used by optional third-party tools, package managers, and developer software on some Macs. /opt

DerivedData DerivedData stores Xcode’s intermediate build products, indexes, and debug artifacts created while compiling and running projects. Xcode Junk · ~/Library/Developer/Xcode/DerivedData

Archives This folder stores Xcode archives of built apps, often used for distribution, notarization, symbol retention, and restoring older build outputs. Xcode Junk · ~/Library/Developer/Xcode/Archives

iOS DeviceSupport Xcode’s iOS DeviceSupport folder stores device support files used when connecting iPhones or iPads for development and debugging. iOS Device Support · ~/Library/Developer/Xcode/iOS DeviceSupport

CoreSimulator CoreSimulator stores data for Xcode’s iPhone, iPad, Apple Watch, and other simulator runtimes used during app development and testing. Simulator Devices · ~/Library/Developer/CoreSimulator