Dev Mode: developer and AI cleanup

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Dev Mode is a separate tab in SpaceUp Mac for developer and AI cleanup. It finds the caches and build output your tools leave behind, things like Xcode DerivedData, npm and Homebrew caches, and forgotten node_modules folders, and clears only what those tools rebuild on their own. Local AI models are listed with their sizes but never deleted. That call stays with you.

What Dev Mode finds

Dev Mode runs its own scan, separate from the main Clean tab, and groups the results into four buckets. Every item shows its real size and a one-line note on how it comes back.

Xcode and Apple tooling

DerivedData in ~/Library/Developer/Xcode/DerivedData, iOS DeviceSupport symbols, simulator caches and Xcode’s own cache folder. Xcode rebuilds all of it the next time you build or plug in a device. Old Xcode archives are listed too, but flagged for review, since you may still need them to symbolicate old crash logs.

Package manager caches

npm (~/.npm), pnpm, Yarn, Bun, pip, uv, Cargo, Gradle, Maven, the Go build cache, Composer, CocoaPods, the Dart and Pub cache (~/.pub-cache) and Homebrew downloads, among others. These are downloaded copies of packages. The manager re-fetches whatever the next install actually needs.

Build output inside your projects

Dev Mode walks your home folder for rebuildable artifacts: node_modules, Pods, .next, .venv, __pycache__, Terraform providers and more. Each folder is listed per project with its size, so you can keep the repo you’re working in and clear the three you abandoned last year. Folders with generic names like build and target only count when they sit next to a project marker like package.json, and they start unticked so you confirm each one yourself.

Editors and AI apps

The web caches kept by VS Code, Cursor, Windsurf and the Claude desktop app. Settings, extensions and chats stay. Plus re-downloadable AI caches: the Hugging Face hub cache (your login token is left alone), PyTorch checkpoints, Keras weights and conda package downloads, not your environments. The AI caches start unticked because they’re large and slow to refetch. You decide whether the disk space is worth the re-download.

Local AI models are never auto-deleted

If you run Ollama, LM Studio, DiffusionBee, Draw Things, ComfyUI, Stable Diffusion WebUI or Stability Matrix, Dev Mode shows each model store with its on-disk size. That’s all it does. These folders mix re-downloadable weights with things no cleaner should touch, like models you trained or merged, so SpaceUp Mac opens them in Finder and leaves the decision to you. There is no checkbox that deletes a model.

The rules

  • Nothing is removed until you approve it on the review screen. Safe items come pre-ticked; anything that needs judgment starts unticked.
  • Approved items are cleared directly rather than moved to the Trash, because trashing gigabytes of rebuildable cache would just move the problem. More on that split in Why Trash first.
  • Dev Mode never touches source code, git history, AI chat memory, credentials or signing keys.
  • The test behind every item is simple. If your tools can’t rebuild it, SpaceUp Mac doesn’t touch it.

You can do this by hand

The biggest wins are one command away, and you should know them:

rm -rf ~/Library/Developer/Xcode/DerivedData
npm cache clean --force
brew cleanup --prune=all

That works, costs nothing, and covers the classics. Dev Mode is for when you want every toolchain in one list, sized and sorted, without remembering fifteen commands. One real scan found 117.45 GB of junk.

Who Dev Mode is for

Anyone whose Mac builds software or runs AI tools: iOS and Mac developers drowning in DerivedData, web developers with years of node_modules, Python and ML folks with model caches they forgot existed. For the background first, start with developer junk on a Mac and where AI apps hide their storage. Both guides walk the manual route as well as what Dev Mode automates.

Stuck on something? Email [email protected] and you will get a fast, human answer.