Summary
The paper designs a blockchain-based procurement IS that navigates the extended blockchain trilemma (decentralization, scalability, security, plus privacy) while preserving privacy, deriving five evaluated design objectives and two design principles: balance decentralization, scalability and security via a public chain plus Layer-2 scaling and decentralized inter-layer communication; and maintain that balance when privacy is required via efficient, resilient cryptography and minimized control points.
Artifact
A public-permissionless, Layer-2 (rollup) blockchain-based procurement information system built on the Aztec privacy-preserving roll-up over Ethereum. Private functions execute off-chain in each user's Private Execution Environment (PXE), which generates zero-knowledge proofs (zk-SNARKs, via the PLONK protocol) attesting to the correctness of procurement actions without revealing prices, quantities, or counterparty identities; a sequencer network verifies and batches these proofs for finality on Ethereum L1. The prototype tokenizes purchase orders as regulation-compliant stablecoins (issued by a licensed financial institution under MiCAR), and orchestrates the procure-to-pay workflow (supplier discovery, private negotiation, ordering, settlement) through L1 (Solidity) and L2 (Noir) smart contracts, including Token, Token Portal, Inbox/Outbox/Rollup, Token Bridge, and Trade contracts.