Free Up Disk Space on a Mac: The Developer's Guide

First: find out who the offenders are

Run these and prepare to be annoyed:

du -sh ~/Library/Developer 2>/dev/null
du -sh ~/Library/Caches 2>/dev/null
du -sh ~/.npm ~/.gradle ~/.cargo ~/.m2 ~/.cocoapods 2>/dev/null
du -sh ~/Library/Caches/Homebrew 2>/dev/null

On a working developer's machine these six lines alone commonly report 50–200 GB — nearly all of it regenerable.

The cleanup, ecosystem by ecosystem

Xcode & iOS development BIGGEST WIN

rm -rf ~/Library/Developer/Xcode/DerivedData
xcrun simctl delete unavailable

DerivedData is pure build state; deleting it costs you one full rebuild per project. Unavailable simulators are dead weight from old Xcode versions. The full breakdown — including DeviceSupport, archives and simulator runtimes — is in our dedicated Xcode guide.

JavaScript: npm, Yarn, pnpm SAFE

npm cache clean --force
yarn cache clean
pnpm store prune

These are download caches — packages re-download on the next install. Old node_modules folders in finished projects are a separate (and often bigger) story; see the JavaScript cache guide.

Homebrew SAFE

brew cleanup --prune=all
brew autoremove

Removes downloaded bottles for everything already installed and uninstalls orphaned dependencies. Often worth 5–15 GB on a long-lived install.

Android & JVM: Gradle, Maven SAFE

rm -rf ~/.gradle/caches
rm -rf ~/.m2/repository

Both re-download dependencies on the next build. Expect the first build afterwards to be slow. Android Studio also keeps AVD system images under ~/.android/avd — delete emulators you no longer use from Device Manager.

Python: pip, virtualenvs SAFE

pip cache purge

Stale virtualenvs and conda environments from abandoned projects are the bigger fish — each can be hundreds of MB. They live wherever you created them (.venv folders, ~/miniconda3/envs).

Rust & Go SAFE

cargo cache --autoclean   # needs: cargo install cargo-cache
go clean -modcache

Rust's target/ directories inside project folders are routinely multi-GB each — cargo clean inside a project wipes its build artifacts.

Docker CHECK FIRST

docker system df          # see what's reclaimable first
docker system prune       # stopped containers, dangling images, networks
docker builder prune      # build cache

CocoaPods SAFE

pod cache clean --all

What not to delete

• Xcode Archives — they hold the dSYMs you need to read crash reports from App Store versions.
• Docker volumes — databases, not caches.
• Downloaded LLM models (Ollama, LM Studio) — re-downloading 40 GB of weights hurts. Delete deliberately, not in a sweep. More in the AI tools guide.
• Anything holding credentials or sessions — config files, cookies, keychains. A glob that drifts too wide can log you out of everything.

Keeping it clean without thinking about it

The honest problem with the commands above isn't running them — it's remembering to. Caches grow back silently, and six months later you're staring at "Your disk is almost full" again.

FAQ

Why is my Mac full when I barely store files?

Because dev toolchains cache aggressively and never clean up. Build intermediates, package downloads and old simulators hide in ~/Library and dotfolders where Finder doesn't show them.

Is macOS "purgeable" space the same thing?

No. Purgeable space is what macOS itself can evict (iCloud-synced files, system caches). Dev caches don't count as purgeable — the OS has no idea your DerivedData is regenerable. You have to clean it yourself.

How much can I realistically get back?

First cleanup on a machine that's never been cleaned: typically 30–100 GB. DevCleaner's anonymous community counter has tracked hundreds of GB freed since launch, averaging roughly 7 GB per cleanup.