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· 3 min read

Dammeli

dammeli

Getting paid back by a friend usually means a screenshot of your IBAN, a “which app do you even have?” back-and-forth, or digging up some old payment link from months ago.

dammeli is one link that holds every way you accept money — Satispay, Revolut, PayPal, bank transfer, whatever else you use. You send it once, whoever’s paying picks what works for them.

The twist: your page is encrypted in your own browser before anything leaves it. The server only ever stores an unreadable blob. No account, no email, nothing tracked. Not even I can read what’s on your page.

How it works

  1. Add the payment methods you already use.
  2. They’re encrypted on your device — the key never leaves your browser.
  3. Share the link: the key travels inside the URL fragment (#...), which browsers never send to the server. No key, no page.

Under the hood

  • AES-GCM with keys derived from a 128-bit secret generated by crypto.getRandomValues
  • Separate read and edit links: the read link can decrypt, but can’t modify
  • Every page is padded to exactly 4096 bytes, so the server can’t even guess how many methods you have
  • All the cryptography lives in a single public/crypto.js, served byte-identical to the repo: anyone can diff it
  • Strict CSP, zero external resources: no CDN, no remote fonts, no trackers
  • A link created today must keep opening forever — every format version stays readable

Features

  • Satispay, Revolut, PayPal, IBAN + up to 5 custom methods
  • Paste-tolerant inputs (full PayPal URLs, IBANs with spaces…)
  • QR code generated locally
  • Share on WhatsApp in one tap
  • “Your pages” list, saved only on your device
  • Dark mode 🌗
  • Italian, English and Spanish 🇮🇹 🇬🇧 🇪🇸

Tech Stack

  • Frontend: Astro (fully static), Tailwind v4, no JS framework
  • API: Netlify Functions
  • Database: Supabase (it only sees encrypted noise)
  • Hosting: Netlify

Still in private beta (0.9) — PRs and feedback welcome!