secp256k1: secp256k1 (Elliptic Curve Library for libbitcoin) secp256k1: secp256k1: Optimized C library for EC operations on curve secp256k1. secp256k1: secp256k1: secp256k1: secp256k1: secp256k1: Project URL: https://github.com/libbitcoin/secp256k1 secp256k1: secp256k1: secp256k1: