Chapter Companion

#ChapterCompanion

Chapter Companion du chapitre Springer. Le code Qiskit et Ethereum n’est pas modifié. La démo est à côté.

Benoît Prieur (2026). Quantum-Backed Integrity for Industrial Blockchain Events: A Secure Logging Framework Using Qiskit and Ethereum. In Frédéric Barbaresco and François Gerin (eds), Quantum Engineering Sciences and Technologies for Industry and Services, QUEST-IS 2025. Communications in Computer and Information Science, vol. 2744, pp. 346–351. Springer, Cham.
https://doi.org/10.1007/978-3-032-13855-2_32

QUEST-IS, EDF Lab Paris-Saclay.

A very simple live demo here https://medialoco.github.io/quantum-secure-blockchain/. This page matches chapter-companion-0.1.2. The circuit library is RustQIP.

Two trees

	Chapter code	Demo
Where	repository root	demo/ and docs/
Measurement	Qiskit Aer, qrng.py	RustQIP
Ledger	Solidity QSecure on Hardhat	the same rules, in Rust
Browser		WebAssembly

The fingerprint is shared:

SHA-256( UTF-8( decimal(timestamp) + "|" + decimal(quantumProof) + "|" + metadata ) )

test/vectors.json freezes three messages. The demo tests read that file.

Chapter code

Python 3.12 and Node.js 20. Qiskit 2.5 does not target Python 3.14.

python3.12 -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt
npm install
npm test
npm run log

npm run log deploys QSecure on Hardhat’s in-process network, draws one Aer shot, and checks the on-chain fingerprint. A persistent node:

npx hardhat node
npx hardhat run scripts/setQuantum.js --network localhost

EVENT_METADATA and EVENT_TIMESTAMP override the event. QRNG_PYTHON overrides the interpreter. The Python checks:

.venv/bin/python -m unittest tests.test_qrng

Qiskit prints qubit 0 on the right. The integer is that bitstring read as a binary number. loggedAt is block.timestamp and is not part of the hash.

This path is a classical simulation of the circuit on Aer, then a local Hardhat chain. It is not a physical quantum source, and it is not a public Ethereum network.

Demo

RustQIP runs the same eight-qubit circuit: one Hadamard per qubit, one measurement. The first qubit is the least significant bit. The page draws one shot when it opens and shows the SHA-256 of that event. Hardhat stays with the chapter code.

cargo test --manifest-path demo/Cargo.toml
wasm-pack build demo --target web --release --out-dir ../docs/pkg
rm -f docs/pkg/.gitignore
npm run demo

Then open http://127.0.0.1:4173. docs/pkg/ is the build already published with the site, so the page works without a local Rust install.

Releases

Demo releases are tagged chapter-companion-x.y.z. The page links to the tag it was built from. These tags package the demo. They do not version the chapter’s Qiskit and Hardhat tree.

Layout

qrng.py                        Qiskit Aer shot
contracts/QSecure.sol          chapter contract
scripts/setQuantum.js          Hardhat logging script
test/                          contract tests and fingerprint vectors
circuits/quantum_circuit.png   the 8-qubit figure
demo/                          RustQIP measurement and fingerprint
docs/                          Chapter Companion page
docs/pkg/                      WebAssembly build of demo/

License

MIT. Cite the paper if you use the code. See CITATION.cff.