Encrypt a private message¶

To encrypt text for another user, pass their public key to your signer. On the receiving side, decrypt using the sender's public key. These calls use NIP-44 by default:

String payload = signer.encrypt("meet at dawn", recipient).await();
String plain = signer.decrypt(payload, sender).await();

If you manage local keys directly, you can derive a conversation key once and reuse it for messages to the same peer:

byte[] conversationKey = Nip44.getConversationKey(
    myPrivateKey, theirPublicKey).await();

String payload = Nip44.encrypt("hello", conversationKey).await();
String plain = Nip44.decrypt(payload, conversationKey).await();

Use the signer methods when you want the same application code to work with local keys, browser extensions and remote signers. To use byte arrays or ByteBuffer values, call the direct helpers instead - but then store and clean up the conversation key yourself.

Encryption produces a payload. To deliver a private message, place it in the event format required by your messaging protocol; NIP-44 itself does not assign an event kind.