- BIP-340 Schnorr signatures over secp256k1 (pure PHP, requires ext-gmp)
- Kind-1 text note events with SHA-256 event ID and tagged hashes
- Raw WebSocket client via stream_socket_client (zero external deps)
- Multi-relay failover: tries each relay until one accepts
- Public key derivation from private key for account display
- Validates 64-char hex private key format and wss:// relay URLs
Authored-by: Moko Consulting