Is it safe to run on a Mac I depend on?
That is the design constraint. Nothing is removed that a scan did not list first, a protected-path policy refuses system and credential stores whatever a category claims, careful and dangerous categories are off by default, and you can send everything to the Trash instead of deleting. Settings changes snapshot the previous value so undo always works.
What does it send?
Nothing. There is no analytics, no crash reporting and no licence phone-home beyond the one-time activation. It works with the network off. The iPhone companion talks only to your own Mac, on your own network.
Which macOS versions?
macOS 14 Sonoma and later, on Apple silicon and Intel. Developed and tested on macOS 27.
Why is the App Store version limited?
App Store apps run in a sandbox. Some of what Systune does — editing launch daemons, running maintenance as an administrator, reading the permission database — is not available to a sandboxed app. The direct build has no such limits. Both are the same code; the App Store build hides what it cannot do rather than failing at it.
Do I need Full Disk Access?
Only for the parts that need it: Safari, Mail and Messages data, and the permission database the audit reads. Systune tells you which settings and categories are affected instead of quietly reporting a default as fact.
How is this different from CleanMyMac or OnyX?
Scope and posture. CleanMyMac cleans and is sold by subscription; OnyX runs maintenance and does not clean or tune; mole is a good command-line tool for reclaiming space. Systune is the only one that puts disk reclamation, a 92-check security audit and 300 macOS settings behind a single window, and it is bought once rather than rented. The difference you will notice first is that it shows you every file it proposes to remove, with size and age, and waits — there is no one-button sweep.
What does it actually delete?
Only what a scan has listed and you have selected. The 79 categories cover app and system caches, logs, crash reports, developer build products (Xcode DerivedData, node_modules, Rust target folders), package-manager caches for a dozen ecosystems, browser and Electron caches, Docker, simulator runtimes, virtual machine images, old language runtimes and toolchains, iOS backups and the leftovers of apps you have uninstalled. Your keychain, iCloud Drive, Photos, Mail and Messages data are refused outright whatever a category claims.
Is there a command-line version?
Yes, and it is not an afterthought — it does everything the app does. Every command takes --json, so it is scriptable and safe to run from cron. There is also a full-screen terminal dashboard for people who live in a terminal. The Mac app, the CLI, the TUI and the iPhone companion all run the same Rust engine.
Is the engine open?
Not yet. The engine is closed source for now, but the review log — five rounds of independent security, correctness and performance review, with every finding and its fix — is written up in full, and I will send it to anyone who asks before buying. The JSON contract all four surfaces speak is documented too.