System Status — refueler share

Zero-knowledge guarantee

✓ Architectural

AES-256 keys are generated browser-side and placed in the URL fragment only. The fragment is never transmitted to our Worker per RFC 3986. We receive and store ciphertext. Reading your files is not technically possible for us.

Anonymous auth

✓ Cashu NUT-00

Upload credentials are blind-signed. The server issues a token without learning its serial number. Transfers cannot be linked to identity at the ledger layer. Double-spend prevention via Supabase spent-token table (NUT-07).

Chunk integrity

✓ BLAKE3 (browser)

Each 50 MB chunk is BLAKE3-hashed client-side via a compiled WASM module loaded from a local bundle. Hash roots enable byte-exact resume on interrupted transfers without restarting from chunk 0.

Passphrase gating

✓ NUT-11 Mode 1

Share links can require a passphrase. The SHA-256 hash of the passphrase is stored in the transfer manifest. The Worker issues a time-scoped download token only on hash match. The passphrase never travels the wire in plaintext.

Server-side chunk verification

⚠ Known gap

The Worker verifies chunk receipt but does not re-verify the client-declared BLAKE3 hash server-side. A compromised client could declare a hash mismatch undetected. Fix: compile BLAKE3 to a static WASM binary in the Worker. No integrity or audit claims are made until this is resolved.

Storage ephemerality

✓ R2 lifecycle

Hard expiry enforced by Cloudflare R2 lifecycle rules: all objects deleted after 92 days maximum. Incomplete multipart uploads aborted after 1 day. No manual deletion required. No exceptions.