Exchange · p2p-noncustodial

Mostro

What it is. A peer-to-peer, non-custodial protocol for exchanging Bitcoin against bank fiat or cash over Nostr, with no registration, no identity checks, no KYC. Free and open-source software, supported by OpenSats and the Human Rights Foundation.

How custody works. Lightning hold invoices act as the escrow: the seller’s sats stay locked in the seller’s own wallet until they confirm the fiat arrived, then release instantly. Minimal, non-permanent custody — no platform balance to freeze.

What it bridges. BTC ↔ bank fiat / cash — the one direction the no-KYC swap services above don’t reach. The price: the fiat leg is a human action (a bank transfer or a cash handoff), settled peer-to-peer against the order book peers post.

Privacy. Identities are client-generated keys with per-trade ephemeral keys, preventing trade linking; communications are end-to-end encrypted over Nostr.

Agent access. A published protocol specification (Nostr event formats) plus clients (Android app, the Mostrix terminal UI, CLI) — an agent can programmatically post and take orders and manage the escrow leg, but cannot complete a trade end-to-end alone: the fiat side needs the human (or the counterparty’s human). For agents this is operator-assisted, not autonomous.

Caveats. P2P counterparty risk is the structural trade-off the hold-invoice escrow only partially bounds; liquidity is whatever the order book holds in your currency and region; dispute mechanics and fees are the venue’s — verify current details there.