[PROPOSAL] RFP-004 — StreamDEX: Privacy-Preserving DEX on LEZ

[kingskuan]

StreamDEX: Privacy-Preserving DEX on LEZ

Summary

This PR implements StreamDEXCore, a privacy-preserving decentralized exchange protocol for the LEZ ecosystem. The implementation introduces zero-knowledge proof-based order matching with support for shielded and private asset transactions, enabling confidential trading while maintaining cryptographic security and verifiability.

Changes

• Core Protocol: Implemented StreamDEXCore with event-driven architecture for order lifecycle management
• Privacy Primitives: Added support for three privacy levels (transparent, shielded, private) via commitment schemes and zero-knowledge proofs
• Order Structure: Defined PrivateOrder interface with commitments for amount, asset, and price, alongside ZK proof validation
• Cryptographic Security: Integrated nullifier tracking to prevent double-spending and replay attacks
• Type Safety: Established AssetInfo interface for asset metadata management with configurable privacy parameters

Testing

• Unit tests for order commitment generation and nullifier uniqueness
• Integration tests for order matching with ZK proof validation
• Privacy level verification across transparent, shielded, and private modes
• Cryptographic security tests for hash collision resistance and proof correctness

Bounty Reference

[PROPOSAL] RFP-004 — StreamDEX: Privacy-Preserving DEX on LEZ

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Submitted for bounty: $56,000