Use signatures with XMTP

With XMTP, you can use various types of signatures to sign and verify payloads.

Sign with an external wallet

When a user creates, adds, removes, or revokes an XMTP inbox’s address or installation, a signature from an external wallet is required.

Sign with an XMTP key

You can sign something with XMTP keys. For example, you can sign with XMTP keys to send a payload to a backend.

const signature = client.signWithInstallationKey(signatureText);

Verify with the same installation that signed

You can also sign with XMTP keys and verify that a payload was sent by the same client.

const isValidSignature = client.verifySignedWithInstallationKey(signatureText, signature);

Verify with the same inbox ID that signed

You can use an XMTP key’s installationId to create a signature, then pass both the signature and installationId to another installationId with the same inboxId to verify that the signature came from a trusted sender.

const isValidSignature = client.verifySignedWithPrivateKey(signatureText, signature, installationId);