Qweb4.py

Quantova Post-Quantum Web4 Client — Python SDK. Connect to a Quantova node, manage post-quantum accounts, sign and broadcast transactions, and interact with QVM smart contracts from Python. The Python counterpart of Qweb4.js and Qweb4.rs.

Quantum security

Quantova is a post-quantum Layer-1. Accounts use NIST post-quantum signatures (Falcon-512, SPHINCS+ SHAKE-128s, CRYSTALS-Dilithium2/ML-DSA-44) with SHA3-256 — no ECDSA/secp256k1 — so they resist quantum attacks. Addresses are Bech32m Q1...; the chain speaks q_* JSON-RPC.

Cross-SDK compatibility (byte-for-byte)

Accounts derive identically to Qweb4.js and Qweb4.rs, so **the same mnemonic yields the same Q1... address** in all three SDKs:

• mnemonic -> 32-byte seed = substrate mini-secret

PBKDF2-HMAC-SHA512(BIP-39 entropy, "mnemonic", 2048)[:32] — verified equal to Qweb4.js ("test test ... junk" -> 4ca479f5...3b4709c).

• address = SHA3-256(public_key)[:20] with byte 0 = 0x40, Bech32m-encoded Q1....
• keypairs use the same post-quantum cores as the node and Qweb4.js: Falcon-512

(ChaCha20Rng(seed)), Dilithium2/ML-DSA-44 (keygenfromseed), SPHINCS+ SHAKE-128s (blake2_256-derived components).

Install

pip install qweb4

Post-quantum backend

The pure-Python package ships the full client (accounts, addresses, ABI, QNS, RPC, fees, contracts) and the mnemonic/address derivation above. **Key generation and signing require a post-quantum backend** exposing the falcon-wasm-style interface (<scheme>pairfromseed / sign / _verify). Register it once at startup:

import qweb4.crypto_backend as cb
cb.setbackend(mypq_backend)   # adapter over the Quantova PQ cores

Any backend that produces the **same Falcon-512 / ML-DSA-44 / SLH-DSA-SHAKE-128s keys from a seed** as Qweb4.js keeps addresses and signatures cross-compatible. (The recommended adapter wraps the same fn-dsa / fips204 / fips205 cores used by Qweb4.rs, so derivation stays byte-identical.)

Quick start

from qweb4 import QWeb4
q = QWeb4("https://rpc.quantova.org")
acct = q.wallet.import_mnemonic("test test ... junk")   # -> same Q1... as Qweb4.js/rs
print(q.rpc.get_balance(acct.address))

Resources

• 🌐 https://quantova.org · 🔎 https://qvmscan.io · 💻 https://github.com/Quantova/Qweb4.py

License

BUSL-1.1 - (c) 2026 Quantova Inc. See LICENSE.