Privacy statement

How Tack handles your data: it doesn't. Images and coordinates stay on your device. We collect anonymous, cookie-less page-view analytics only.

In one sentence

tack. runs entirely in your browser. Your images, the points you draw, and the JSON or YAML you export never leave your device — there is no server-side processing of any kind. The only data we collect is anonymous, cookie-less page-view analytics so we know the site is reaching people.

What “on-device” means here

When you load an image into tack.:

  • The image is read straight into your browser’s memory by the file picker or drag-and-drop API. It is not uploaded to any server.
  • Every point you mark, every polygon you draw, and every bezier handle you adjust is computed locally in your browser by JavaScript that runs on your machine.
  • When you click Generate, Copy, or Download, the resulting JSON or YAML is built locally and either copied to your clipboard or saved to your device’s Downloads folder. Nothing is transmitted.
  • If you load existing JSON to edit, it is parsed locally the same way.

There is no account, no login, no upload, no cloud sync, no session persistence on a server. We do not need any of those things to deliver the tool, and we have not built them.

What we do collect

We use Umami — a privacy-focused, open-source analytics tool — running on a self-hosted install we operate ourselves, to record anonymous page-view events only. Each event captures:

  • The URL you visited (/, /privacy/, /terms/).
  • An anonymized referrer (where you came from).
  • Your browser, operating system, and screen size, derived from the standard User-Agent string.
  • An approximate country, derived from your IP address.

Because we self-host the Umami instance, the page-view data stays on infrastructure we control — it is not shared with a third-party analytics vendor.

We do not collect:

  • Your IP address (it is discarded after the country lookup and never stored).
  • Cookies. Umami is cookie-less by design.
  • Any cross-site tracking identifier.
  • Anything you type, draw, paste, or load into the tack. tool.
  • Per-button-click telemetry. We deliberately do not track individual interactions inside the app.

Local storage and your device

tack. does not currently write anything to localStorage, sessionStorage, IndexedDB, or cookies under its own domain. The only browser storage we use is the service worker cache, which stores the static files that make up the site (HTML, CSS, JavaScript, fonts, icons) so the app can run offline. You can clear this at any time from your browser’s site-data settings.

Third-party services

  • Umami — anonymous, cookie-less page-view counter. We run Umami on a self-hosted install; the data does not leave our infrastructure.
  • Google Fonts — Manrope and JetBrains Mono are loaded from fonts.googleapis.com and fonts.gstatic.com. When your browser fetches these, Google receives the request metadata (IP, user-agent, the requested font URL). policies.google.com/privacy
  • Cloudflare Pages — the site is hosted on Cloudflare’s edge network. Cloudflare may keep short-term server logs for security and abuse-prevention purposes. cloudflare.com/privacy

We do not use Google Analytics, Meta pixels, advertising trackers, behavioural retargeting, or session-replay tools.

Your rights

Because we do not store personal data, there is nothing for us to give you, correct, or delete. The aggregate analytics counts cannot be tied back to you.

If you would like the site to work without ever contacting the analytics endpoint, install an ad blocker or privacy extension — tack. itself will continue to work normally.

Changes to this statement

If we ever start collecting more data, we will update this page and the Last updated date below before the change takes effect. Material changes will be reflected in the site’s footer for at least 30 days.

Contact

Questions or concerns: write to [email protected].