TrimMyMac

A lightweight macOS menu-bar cleaner that never deletes anything — it only moves to Trash.

Memory & disk at a glance, plus junk cleanup, duplicate finding, and app uninstalling — built around a strict, test-enforced safety model.

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What it does

TrimMyMac sits in your menu bar as the squeegee glyph next to MEM x% · SSD y%, and opens a popover with four tools.

Tool	What it does
Menu-bar monitor	Live memory pressure + disk usage. Metrics match exelban/stats: memory used = active + inactive + speculative + wired + compressed − purgeable − external, SSD used% = (total − availableImportant) / total.
Junk cleanup	Scans user caches, logs, and developer junk under your home directory and lets you review before trashing.
Duplicate finder	Folder-scan duplicate review. Collapses hard links and probes APFS clones — clones are surfaced but never auto-selected.
App uninstaller	Drop a .app → finds its leftovers (caches, preferences, app-support, containers) → trashes them. Exact bundle-ID matches are auto-selected; ambiguous matches require your confirmation.
Memory card	Read-only. Shows pressure and a breakdown — there is no "purge"/"free RAM" button by design.

Safety model

Every destructive path goes through SafeRemover and is covered by tests. The six invariants:

1. Trash-only — items are moved to Trash (NSWorkspace.recycle), never removeItem. Nothing is unrecoverable.
2. You-chosen targets, no blanket sweep — junk scanning is confined to ~; the duplicate finder scans the folder you pick; the uninstaller trashes the .app you select plus its ~/Library leftovers (so it reaches /Applications by design). There is no whole-disk sweep — every target is one you chose, and the scan never follows symlinks out of the chosen root.
3. TOCTOU guard — each selected item is re-stat'd at its own path immediately before trashing (identity/size/mtime/device); if that drifted since the scan, it's skipped. This guards the item itself, not a deep content-diff of a directory tree.
4. Hard-link & clone safety — hard links are excluded; APFS clones are never auto-selected.
5. Exact-match uninstall — only exact bundle-ID leftovers are auto-selected; anything ambiguous is left for you to decide.
6. Memory is read-only — no purging, no swapping, no "speed up your Mac" tricks.

Requirements

• macOS 26 (Tahoe) on Apple Silicon
• Swift 6 toolchain — works with Command Line Tools only (full Xcode not required)
• Some scans need Full Disk Access (granted via System Settings → Privacy & Security). If a scan can't read a location, the app flags it instead of silently under-reporting.

Install (for users)

Not building from source? Download a release and install it on your Mac — see the 설치 가이드 / Install guide. It covers the download, the first-launch Gatekeeper prompt (the app is self-signed, not yet notarized), and permissions.

Build & install (from source)

./scripts/build-app.sh

This compiles a release build, assembles TrimMyMac.app (with AppIcon.icns), code-signs it, and installs to /Applications/TrimMyMac.app. Then:

open /Applications/TrimMyMac.app

Code signing

The build looks for a self-signed identity named TrimMyMac Self-Signed. With it, the app's Designated Requirement stays constant across rebuilds, so Full Disk Access survives rebuilds. Without it, the build falls back to ad-hoc signing — functional, but FDA must be re-granted on every rebuild. See docs/codesign-setup.md to create the identity once.

Running tests

Tests use Swift Testing (not XCTest, which Command Line Tools don't ship). Plain swift test silently skips them — use the wrapper, which adds the required framework search path:

./scripts/test.sh

106 tests across 16 suites cover the safety invariants and core logic.

Architecture

Sources/
  TrimCore/          # pure, testable engine — no UI
    SafeRemover, JunkScanner, DuplicateFinder, AppUninstaller,
    MemoryMonitor, DiskMetrics, StatProbing, IgnoreRules, …
  TrimMyMacApp/      # SwiftUI + AppKit menu-bar app
    TrimMyMacApp.swift     # @main, MenuBarExtra + windows
    MenuBarView.swift      # menu-bar label + popover
    MenuBarIconAsset.swift # embedded template glyph (squeegee)
    Panels/                # Junk / Duplicate / Uninstall panels

All cleanup logic lives in TrimCore so it can be unit-tested without a UI; TrimMyMacApp is a thin SwiftUI shell. The app is a menu-bar agent (LSUIElement) — no Dock icon.

License

MIT © 2026 BYEONGHUN HWANG. Personal project.