NIP-90 DVM Directory

How to send a DVM job (Python)

Copy this to send a text-to-text query (kind 5050) with a bid commitment:

import json, time, hashlib, os, ssl, websocket, ecdsa

# BIP-340 Schnorr signing — required for Nostr
def tagged_hash(tag, msg):
    h = hashlib.sha256(tag.encode()).digest()
    return hashlib.sha256(h + h + msg).digest()

def sign_event(event, privkey_hex):
    serial = json.dumps([0, event['pubkey'], event['created_at'],
                         event['kind'], event['tags'], event['content']],
                        separators=(',',':'), ensure_ascii=False)
    event['id'] = hashlib.sha256(serial.encode()).hexdigest()
    msg = bytes.fromhex(event['id'])
    seckey = bytes.fromhex(privkey_hex)
    p = ecdsa.SECP256k1.generator; n = ecdsa.SECP256k1.order
    d = int.from_bytes(seckey, 'big')
    P = d * p
    if P.y() % 2 != 0: d = n - d
    t = (d ^ int.from_bytes(tagged_hash("BIP0340/aux", os.urandom(32)), 'big')).to_bytes(32, 'big')
    pk = P.x().to_bytes(32, 'big')
    k0 = int.from_bytes(tagged_hash("BIP0340/nonce", t + pk + msg), 'big') % n
    R = k0 * p; k = k0 if R.y() % 2 == 0 else n - k0
    e = int.from_bytes(tagged_hash("BIP0340/challenge", R.x().to_bytes(32,'big') + pk + msg), 'big') % n
    event['sig'] = (R.x().to_bytes(32,'big') + ((k+e*d)%n).to_bytes(32,'big')).hex()
    return event

job = {
    'pubkey': YOUR_PUBKEY_HEX,
    'created_at': int(time.time()),
    'kind': 5050,
    'tags': [
        ['i', 'What is the Riemann hypothesis?', 'text'],
        ['bid', '21000'],  # 21 sats in millisats
    ],
    'content': '',
}
job = sign_event(job, YOUR_PRIVKEY_HEX)
ws = websocket.create_connection('wss://relay.damus.io', ...)
ws.send(json.dumps(['EVENT', job]))

The DVM replies with kind 7000 (feedback) and kind 6050 (result). Subscribe to {'kinds': [6050, 7000], '#p': [your_pubkey]} to receive responses.

Full guide: Building a NIP-90 DVM