DiskWise

The rule that shapes everything else

DiskWise has exactly one deletion path: the system’s trash API. Nothing it does removes a file outright. Everything lands in the Trash, the session keeps an undo stack so a mistaken removal can be reversed for as long as the app is running, and emptying the Trash is left to Finder — which means macOS asks you one more time before the space is really gone.

Two consequences follow from that. Home and ~/Library can never be removed wholesale, only reviewed. And in the sandboxed Mac App Store build the app cannot even ask Finder to empty the Trash, because the sandbox blocks the event; the README says this was measured, not assumed, so that build’s Empty button opens the Trash and leaves you to press ⌘⇧⌫.

What it looks at

The overview walks the whole volume and draws it as a single ring, with a ledger beside it. Each slice is a block of bytes the scan actually measured, and the slices are meant to add up to the whole disk: top folders, everything else counted, what was not measured, purgeable space and free space. A coverage line names what the scan missed — system volumes, admin-only folders and anything blocked on Full Disk Access — rather than quietly reporting a smaller number.

Below that sit the tools people actually open it for:

• App Caches and Dev Caches — a curated knowledge base with a per-entry explanation of what the cache is, what happens if you delete it and how it comes back, plus a badge grading the cost as Safe, re-downloadable or data loss. The developer caches cover Homebrew, npm, pnpm, yarn, Maven, Gradle, conda, uv, cargo, Ollama models, Xcode archives, DerivedData and every simulator device listed individually.
• node_modules — grouped per project, so the report reads “these 3 checkouts cost 4.7 GB” rather than listing directories.
• Docker Usage — one row per container runtime actually installed (Docker Desktop, OrbStack, Podman, colima), measured as the space its virtual disk takes. Read-only: it points at where to prune instead of pretending it can delete a single image.
• Large Files, Long Untouched and Duplicates — duplicates are grouped through a size, partial-hash then full-hash pass, and the newest copy in each group is locked so the only copy cannot be removed. Copies inside a venv, site-packages or DerivedData are excluded from the comparison and listed separately, because deleting one of those breaks an environment.
• Leftovers — data orphaned by apps that are already gone, matched against the bundle IDs of what is still installed, deliberately under-reporting.

The README is explicit that the cache list only explains entries the developers understand, so some rows carry an explanation and some do not.

Build, distribution and the two builds

DiskWise is written in Swift and SwiftUI with no Electron shell, no Python sidecar and no local server. The build script defaults to Apple Silicon; passing ARCH=universal produces the universal file, and from version 1.3 every published disk image is universal, so one download works on Apple Silicon and Intel. The same source builds either a sandboxed App Store app or a direct build, and the two differ in observable ways — the direct build can ask Finder to empty the Trash, the sandboxed one cannot, and the direct build’s scan reaches the whole volume while the sandboxed one reaches what its grant allows.

That gap is also why the store version lags: the GitHub release is 1.7 while the App Store listing is still 1.5. Anyone who wants the current version, the wider scan or the working Empty button should take the direct download or the Homebrew cask.

Themes as data

The six themes — Morning Fog, Graphite, Mint, Polar Night, Aurora Glass and Ink & Paper — are not colour swaps. Each changes the typeface, corner radius, elevation, motion signature and chart palette, and all six live in a single skins.json file that documents its own fields. A seventh theme is one JSON object added through a pull request, with no Xcode, no build and no Swift required.