Precompiles

Call Mercury EVM precompiles from Python

Mercury EVM ships with precompiles for common cryptographic operations. They're callable via eth_call — no encryption state needed, just a Web3 instance connected to a Seismic node.

from seismic_web3.precompiles import (
    rng, ecdh, aes_gcm_encrypt, aes_gcm_decrypt, hkdf, secp256k1_sign,
)
from seismic_web3 import Bytes32, PrivateKey, CompressedPublicKey

# On-chain random number generation
random_val = rng(w3, num_bytes=32)

# On-chain ECDH key exchange
shared_secret = ecdh(w3, sk=my_private_key, pk=their_public_key)

# On-chain AES-GCM encrypt / decrypt
ciphertext = aes_gcm_encrypt(w3, aes_key=key, nonce=1, plaintext=b"secret")
plaintext = aes_gcm_decrypt(w3, aes_key=key, nonce=1, ciphertext=bytes(ciphertext))

# On-chain HKDF key derivation
derived_key = hkdf(w3, b"input key material")

# On-chain secp256k1 signing
signature = secp256k1_sign(w3, sk=my_private_key, message="hello")