Mostro is an open source daemon for peer-to-peer Bitcoin trading over the Lightning Network, built on the Nostr protocol. It is aimed at people who want to buy and sell bitcoin for fiat without depositing funds with a centralized exchange and without handing over identity documents. Operators run the backend, and users interact with it through Nostr clients.
The design choice that matters most is that Mostro does not hold custody of user funds. Trades are coordinated through Lightning hold invoices, so the money moves between the two parties rather than sitting in a platform wallet. Because Nostr relays are censorship-resistant and anyone can run an operator, the network is harder to shut down than a single company's servers. Read the project's documentation and FAQ before your first trade to understand the mechanics.
What Is Mostro and Who Is It For?
Mostro is a marketplace layer that sits on top of two protocols. Nostr provides the messaging and identity layer, where orders are published as signed events and relays pass them along. The Lightning Network provides fast, low-fee payments that can be locked with a hold invoice until both sides confirm the trade.
The people most likely to benefit are bitcoiners who already run a Lightning wallet and want to buy or sell bitcoin for local currency with a counterparty they meet through an open order book. It also suits users who are uncomfortable with account registration at centralized platforms. It is less suited to someone who wants a polished, support-backed consumer app, because the experience depends on the operator, the client and your own wallet setup.
How a Hold Invoice Trade Works
A hold invoice is a Lightning payment that the receiver's node accepts but does not settle until a secret is revealed. In a Mostro trade, the seller's bitcoin is locked this way while the buyer sends the fiat payment. Once the fiat side is confirmed, the seller releases the secret and the funds settle to the buyer.
If the trade stalls, the order can expire and the locked payment is returned rather than being taken by a middleman. This is the main reason the operator never needs custody. It also means you need a Lightning wallet that supports hold invoices, and you should check that your wallet and the operator both support the features you intend to use before committing funds.
Understanding Nostr Identity and Privacy
Nostr identities are key pairs rather than email accounts. You generate a keypair, and your public key is how counterparties recognize you. No name, phone number or government ID is requested by the protocol. This is the basis for the no-KYC model.
The trade-off is that your key is your identity. If you lose the private key, you lose access to that identity, and if someone obtains it, they can act as you. Keep your private key backed up offline, and consider using a separate identity for trading rather than your main social presence. Privacy also depends on which relays you publish to, so it is worth reviewing that list.
Running Your Own Operator Versus Using One
Most users will simply connect a client to an existing operator. Running an operator is a separate undertaking: it requires a Lightning node with LND, the admin macaroon for hold invoice management, and enough technical skill to keep the daemon online. Operators earn the developer fee on successful trades, and they set their own order limits and supported currencies.
Because anyone can run one, you should compare operators on their fee settings, currency coverage, uptime and dispute handling before choosing. Diversity across operators is one of the network's strengths, but it also means quality varies.
Key features
Developer fee system
RPC admin interface
Background scheduler
Multi-currency support
Optional proof-of-work protection
Opt-in anti-abuse bonds
Supported coins
The project documentation references Bitcoin (BTC) trading over the Lightning Network, with Nostr as the transport layer. Mostro is a bitcoin-only exchange; it does not list other coins for trading.
How to install Mostro on Windows
- 1
Get the official build
Download the program only from the official website or the project's GitHub Releases page. Do not use links from forums or third-party mirrors, since a modified binary can steal funds.
- 2
Verify the file
Compare the SHA-256 checksum of the downloaded file with the value published on the release page, or verify the signature if one is provided. A mismatch means the file should not be run.
- 3
Install and configure the daemon
Follow the documentation to point the daemon at your LND node, including the connection details and admin macaroon. Keep the macaroon private, because it grants control over your node's payments.
- 4
Connect a client
Install a compatible Nostr client or the Mostro mobile client and add the operator you want to use. Confirm that the client and operator are current before placing any order.
-
Test on a local network first
If you are new to Lightning, practice on a regtest setup. Polar is recommended for local testing, letting you run a simulated network with small amounts before any real funds are involved.
System requirements
- A Lightning Network node running LND, with connection details available to the daemon
- An admin macaroon for hold invoice management
- A Nostr-compatible client for placing and tracking orders
How to use Mostro
Using Mostro is a matter of placing or taking an order through a client connected to an operator, then completing the trade step by step. The exact screens depend on your client, but the sequence is consistent across the network.
A typical trade looks like this:
- Choose an operator and check its fee, supported currencies and order limits.
- Create a buy or sell order, or browse the order book and take an existing one.
- If you are selling bitcoin, wait for the hold invoice to be created and paid from your Lightning wallet.
- Send the agreed fiat payment through the method both parties confirmed, and keep the payment record.
- Confirm receipt on the fiat side so the seller can release the secret and the bitcoin settles.
- Check your wallet balance and the audit events to confirm the trade and fee were recorded correctly.
- If something goes wrong, open a dispute through the client and follow the operator's process.
Pros & cons
- No custody of your bitcoin by the operator
- No identity verification or account registration required
- Transparent, configurable fee published as audit events
- Open source under GPLv3, so the code can be inspected
- Decentralized design makes the network harder to shut down
- Requires a Lightning wallet and some comfort with self-custody
- Quality and fees vary between independent operators
- Key management is your responsibility; a lost key means a lost identity
- Disputes depend on the operator's process rather than a central support desk
- Windows support is listed as unverified in the documentation, so check client compatibility
Is Mostro safe?
Mostro handles real bitcoin, so treat it with the same care you would give any wallet. Download only from the official website or the GitHub Releases page, and verify the SHA-256 checksum or signature before running any file. Never enter a seed phrase, private key or macaroon on a third-party website, and be wary of anyone who asks for them in a direct message.
Antivirus software may flag Lightning and daemon-style tools as suspicious. Investigate any warning instead of simply dismissing it, and never disable your protection entirely to get the program running. Also be aware that the latest code update in the project history is dated 2026-10-29, so confirm the current release on the official page before relying on any version.
- Official source only. Download from github.com/MostroP2P/mostro. Ignore ads and lookalike domains.
- Check the SHA-256. Compare the installer hash with the value the developer publishes before running it.
- Never share your seed phrase. No developer, support agent or website — including CryptApps — will ever ask for it.
Alternatives
Mostro differs from the other tools in this catalog mainly in purpose. Vega, Nostrid and Notedeck are general-purpose Nostr clients for reading and posting, while Mostro is a trading protocol that uses Nostr as its order book and messaging layer. Bro App takes a similar Nostr and Lightning approach but focuses on paying bills with bitcoin rather than exchanging fiat for it.
Keychat is a chat application with bitcoin and ecash features, which overlaps with Mostro only where payments are concerned. Mostro Mobile is the closest companion, acting as a mobile front end for the Mostro exchange. If you want to trade rather than chat or browse, Mostro is the relevant choice, and a Nostr client such as Nostrid or Vega can complement it for managing your identity.
Specifications
- Price
- Free
- Type
- Open source
- License
- GPLv3
- Latest version
- v0.20.2
- Last update
- 29 Oct 2026
- Windows support
- Unverified (Windows mentioned in docs)
- Source code
- github.com/MostroP2P/mostro
Frequently asked questions
The software itself is free and open source under GPLv3. Trades carry a developer fee set by the operator, with a default of 0.6 percent per order. Lightning network fees are separate, so check the current fee settings on the operator you use before trading.
No identity verification, registration or personal data is required by the protocol. Your Nostr keypair is your identity. Individual operators could add their own requirements, so review the operator's terms before you start.
No. Trades use Lightning hold invoices, so the operator does not take custody of your funds. The payment settles between the buyer and seller once the trade is confirmed, and an expired order returns the locked payment.
The documentation mentions Windows but marks support as unverified, so confirm your client works on your system first. Download only from the official sources, verify the checksum, and practice with small amounts before trading larger sums.
Running your own operator requires an LND node. Most users connect a compatible client to an existing operator, and your Lightning wallet must support hold invoices to complete trades.
A macaroon is an authentication token for LND. The admin macaroon grants broad control over the node, including payments, so keep it private and never share it with anyone or enter it on an untrusted site.
Yes. The documentation recommends Polar for local testing, which runs a simulated Lightning network. Practicing there lets you learn the trade flow without risking funds.
Open a dispute through your client and follow the operator's process. Because there is no central support desk, keeping records of your payment confirmations and messages will help if a dispute needs resolving.
Verdict
Mostro suits bitcoin users who want a non-custodial, no-KYC way to trade for fiat over the Lightning Network and who are comfortable managing their own keys and Lightning wallet. Its open design and transparent fees are attractive, but the experience depends on the operator and client you choose. Beginners should practice on a test network with small amounts before trading real funds.