Privacy
Last changed 25 October 2026.
Waterline is run by Hadi Diab. It keeps what you put in it so it can show it back to you, and nothing more.
What is stored
- Your name and email, to sign you in and to write to you.
- Your passkey’s public key. The private key never leaves your device.
- Everything you enter about your Household: Accounts, Transactions, Budgets, Recurring Items, Savings Goals, Loans, Holdings, Assets and their history.
- Each sign-in: when, how (passkey or email link) and which kind of device. These are kept 12 months, so you can see your own on Settings.
- One cookie, to keep you signed in. There are no tracking or advertising cookies.
Where
Vercel runs the app and Supabase keeps the database, both in London, United Kingdom. They store and serve it for Waterline and use it for nothing else.
The beta keeps no backups. If something went wrong with the database, what you entered could be lost, so keep your own copy with Export.
Who else receives anything
- Resend sends Waterline’s emails: it receives your email address and the email itself (a sign-in link or an Invite).
- Sentry receives what it takes to find what is slow or broken, identified by a User id, never your email: errors, with the stack trace and the failing line; for one request in ten, how long each part took, with the database queries’ shape but never their values; and Waterline’s own log lines and counts, which are fixed sentences and ids. No request bodies, cookies, headers or form values, no session replay, and nothing it receives carries an amount, a name or a description. It runs in Sentry’s EU region.
- Vercel also counts which pages are opened and measures how fast they load for real visitors, so slow pages can be found: the page’s address without anything after its “?”, the kind of device and browser, and the country. No cookies, and nothing that names you.
- PostHog receives what happened, never the money: “Setup finished”, “Transaction recorded”, identified by a User id, with no IP address. Waterline’s server sends these; no PostHog script runs in your browser. It runs in PostHog’s EU region, and Settings will let you turn it off.
PostHog is not switched on yet. When it is, it receives exactly what is above and nothing else.
Exchange rates and Holding prices come from public sources. Waterline asks them for currencies and ticker symbols, never for anything about you.
Taking your data, and deleting it
Export gives you everything as files at any time. Settings › Delete account deletes you and your Household, with everything in it, at once. With no backups, it is gone at once.
Questions
Write to support@waterline.cash.