A free, open-source Mac app. It finds the dev servers, MCP servers, git worktrees and background jobs your apps and agents left behind, shows what they cost you, and cleans them up safely.
macOS 14 or later · Apple silicon and Intel · Signed and notarized · MIT license
Leftovers adds up what the leftovers are costing you in memory, swap and disk, and shows your Mac's strength now next to what a safe cleanup gives back. On the Mac it was built on: 41% now, 68% after cleanup.
It's an honest estimate, with the formula one click away: half memory available, a third swap, a fifth free disk.
Activity Monitor sorts by memory in RAM. The memory that is actually lost is somewhere else.
A video encoder leaked for four days. Almost all of it had been pushed to swap, so it barely showed up. Leftovers measures the full footprint: RAM, compressed and swapped.
Twelve Claude Code sessions each started their own copy of the same four MCP servers. Dev servers kept running days after their terminal closed.
Leftovers never touches system or root processes. It asks before quitting anything, and checks a process is still the same one before it sends a signal.
Each coding agent grabs something, sets up, and runs off to the next thing. The blocks, the plate and the shoes stay where they were dropped. On a Mac, those are dev servers, builds and MCP servers, and they keep holding memory until someone picks them up.
The needle shows memory in use. The menu shows what to do about it.
Idle processes holding memory they don't use, each with a plain-language reason and a Quit button.
Every app with all of its helper processes added up, so the one hogging memory has a face.
Memory for each Claude Code, Codex, Gemini CLI, Cursor Agent, Aider or OpenCode session, and everything it started.
Memory, swap and disk in one score, now and after a safe cleanup, with the formula shown.
How much is macOS, how much your apps and their data, how much is yours. Then clear the developer caches that rebuild themselves.
AI models, Docker, old node_modules, dead simulators and Time Machine snapshots, each scanned only when you open it.
Finds git worktrees whose work is already on main, squash merges included, and removes them one by one or all at once.
Every background job with its schedule, next run and status, and which agent set it up.
Quit every likely leak at once, after a standard confirmation that lists what will stop.
Open to numbers in well under a second, and each refresh shows how long it took. About 22 MB and no CPU at idle.
No accounts, no telemetry. The only network request is an update check you can turn off. Everything it reads stays on your Mac.
Leftovers splits your disk three ways: macOS itself, the apps you installed with their data and caches, and your own files. Then it offers the caches that rebuild themselves. On the Mac it was built on, Xcode alone was keeping 93 GB of old build files.
A cache is only emptied while nothing using it runs, and your code and documents are never touched.
Advanced goes further: downloaded AI models, Docker images and build cache, old node_modules, simulators that can never start again, and local Time Machine snapshots. And if the disk drops under 10% free, you get one quiet notification a day.
On the Mac it was built on: 40 simulators that could never start again, holding 7 GB. Each Advanced page scans only when you open it.
Agents open a git worktree per task and rarely clean up. Leftovers checks every one: is its work already on main, does it have uncommitted changes, is anything still working in it. It even spots branches that were squash-merged on GitHub, which git itself can't see.
51 of them squash-merged on GitHub. Removable in one step.
Each worktree carries its own dependencies and build output.
The check is read-only, and git refuses to remove a worktree with unsaved work. Branches are kept.
Agents don't just leave processes running. They schedule things: a watcher every 20 minutes, a script every morning. Leftovers lists every background job in your account with a schedule you can read, when it runs next, and whether it's working or failing.
The app is also a command-line tool with the same engine and the same safety rules, so an agent can check memory and clean up after itself.
# add the command once ln -s /Applications/Leftovers.app/Contents/MacOS/Leftovers ~/.local/bin/leftovers leftovers --report # readable summary leftovers --json # likelyLeaks, agents, duplicateToolServers leftovers --clean # quit likely leaks; protected processes are refused leftovers --jobs # scheduled background jobs (add --json) leftovers --worktrees # git worktrees and which are safe to remove (add --json)
Agents that schedule a job can leave a one-line note in ~/Library/Application Support/Leftovers/jobs/<label>.json (purpose, creator, end date), and Leftovers labels the job with it.
Open the disk image and drag Leftovers to Applications. It's signed and notarized by Apple, so it opens without warnings.
brew install --cask arpwal/tap/leftovers
Or build from source with Swift 6: swift build.
No price, no account, no telemetry. If Leftovers gave you back a slow afternoon, a star on GitHub helps other people find it, and following along on X is how you'll hear what's next.