Free, open-source (MIT) macOS disk space analyzer pitched as a faster DaisyDisk alternative: native Swift/SwiftUI sunburst chart under 3 MB, claimed 17s cold scan of a 1 TB APFS drive via bulk getattrlistbulk(2) reads, FSEvents-replay rescans, APFS volume/firmlink/snapshot-aware accounting, purgeable-space and developer-cache (Xcode, npm, Homebrew) cleanup views, instant name search, and a Collector that batches files for move-to-Trash or permanent deletion with system/home/Library folders blocked. Three channels: notarized direct download with Sparkle EdDSA-signed self-updates and Full Disk Access, a sandboxed Mac App Store build limited to picked drives, and a Homebrew cask. Solo security-engineer side project; repo created 2026-07-20, announced on r/macapps 2026-08-03, 21 releases through v1.5.2.
Solo project: 137137137 authored 324 of 329 commits; two external contributors (4 and 1 commits). App Store seller name 'Andrei Golli'. Day job appears to be security engineering; OpenDisk is one of a handful of side repos (Fullbright, docx-editor).
License
MIT
MIT (LICENSE in repo)
Price
Free
Free, MIT licensed, no in-app purchases, no accounts; site FAQ asks only for a GitHub star
Launched
Author's r/macapps announcement (the public debut); v1.0.0 binary was on GitHub 2026-07-22 and the Mac App Store listing went live 2026-08-02
Repo created
GitHub stars
351 (as of 2026-11-02)
First release
Domain registered
(opendisk.app)
Last seen alive
Checks
Mechanical checks derived from the fields above. Each row is one fact; "not yet checked" means exactly that, not a failure. There is no composite score; read them together.
Track record
92 days ago
Source published
Yes
Release signing
Notarized
Security contact
Yes
Reproducible builds
Not yet checked
Telemetry
None
Runs elevated
Never
Auto-update channel
Signed
Recent activity
Last seen yesterday
SECURITY.md (created 2026-09-23, seven weeks after launch) routes reports through GitHub private vulnerability reporting with a promised 7-day reply and 14-day fix window; explicitly scopes Full Disk Access plus file deletion and update-mechanism tampering as report-worthy.
Site: builds 'notarized by Apple, and every update is checked against an EdDSA signature before it installs' - Sparkle on the direct download; Mac App Store edition updates through Apple, Homebrew via brew upgrade.
Privacy claim on site and README: no telemetry, analytics, or accounts; 'the only network request is the update check' (direct-download build).
Runs as the user, never as root: the download asks for Full Disk Access (a TCC grant, not elevation); the App Store build is sandboxed and scans only the drives/folders the user picks.
Deletion guards: permanently delete or move-to-Trash per cleanup; system folders, home folder, and Library are protected.
Launch post: 'a free, open source DaisyDisk alternative ... DaisyDisk ($9.99) is the closest comparison. Same sunburst interaction, and OpenDisk is free, MIT licensed, and faster.'
Same-lane free Swift DaisyDisk alternatives four months apart in the 2026 wave: Radix launched April 2026 as a 'Free DaisyDisk Alternative', OpenDisk followed in July.
Author's earlier Mac utility, promoted on r/macapps from the same reddit account starting September 2025; MIT, not a cleaner.
Research notes
Solo security engineer's side project: GitHub bio reads 'Security Engineer & Researcher' and the reddit account is a years-old personal one (RIT cybersecurity student in 2023, r/crowdstrike detection/RTR tooling questions in 2026) - a working engineer shipping a Mac utility, not a product company.
Fast repo-to-announcement cycle done properly: repo created 2026-07-20, v1.0.0 shipped 2026-07-22, Mac App Store live 2026-08-02, announced on r/macapps 2026-08-03 - two weeks from repo to launch, but with notarized builds, a real site, and a changelog rather than a bare repo.
High release cadence: 21 GitHub releases from v1.0.0 (2026-07-22) through v1.5.2 (2026-10-31); site ships per-version release notes and a changelog.
Security process grew after launch: the repo shipped without a security policy, then gained SECURITY.md on 2026-09-23 with GitHub private reporting, a 7-day acknowledgment promise, and explicit scoping of unintended-deletion and update-tampering reports.
Deletion design is conservative for the category: per-cleanup choice of Trash vs permanent delete, and system folders, home folder, and Library are refused outright.
Performance claims are self-benchmarked: '1 TB cold scan in 17s vs DaisyDisk 37s' on the site and launch post; no third-party verification.
Launch post said 'Requires macOS 26 (Tahoe) or later'; App Store metadata (minimumOsVersion 14.0) and the current site say macOS 14 Sonoma or later - requirement widened after launch.
Earliest author promotion found: repo created 2026-07-20, App Store live 2026-08-02, announced the next day. Post states 'Requires macOS 26 (Tahoe) or later' - App Store metadata and the site now say macOS 14+. Archived locally 2026-11-02.
DaisyDisk has been the go-to for that for years, but it costs $9.99 and you can't see what it's doing. — Problem statement
Free, MIT licensed, no in-app purchases, no accounts, no telemetry. — Virtue
The app is also under 2.5 MB, because it's native Swift with nothing bundled into it. — Tech bingo
The full source is on GitHub if you want to read what it's doing before you give it disk access — Trust signal
I'm the developer. Happy to answer questions or take bug reports here or in GitHub issues. — Engagement hook