jackshen

Developed and maintained crypto custody infrastructure supporting secure digital asset management. Implemented and enhanced Hierarchical Deterministic (HD) wallet functionality for scalable wallet generation and key management. Onboarded new blockchain networks and cryptocurrencies into the custody platform, including integration, testing, and production deployment. Managed and maintained blockchain protocol upgrades, network migrations, and hard forks for existing assets to ensure compatibility with evolving blockchain ecosystems. Developed Kafka-based event-driven services for on-chain transaction monitoring, achieving real-time deposit detection and instant withdrawal confirmations. Developed an AI code agent skill to automate integration of existing blockchain networks with Kafka-based event-driven services, reducing repetitive development effort and improving implementation consistency. Designed and built historical market data pipelines using Azure Blob Storage and Apache Parquet, processing over 2.4 million records daily across 24 scheduled ingestion pipelines to support automated reporting. Streamlined regulatory compliance by integrating Notabene and Satoshi Test solutions, ensuring adherence to Travel Rule requirements across all outgoing transactions.

Developed and optimized blockchain core components, including Proof of Stake (PoS) consensus and fast finality mechanisms to reduce block confirmation time and enhance network performance. Implemented and enhanced blockchain features including multi-signature transactions, staking mechanisms and NFT functionality within the blockchain core. Developed and maintained the Sirius Chain SDK ecosystem, including C++ SDK, Golang SDK and TypeScript SDK to support blockchain application development. Built blockchain monitoring infrastructure using C++ and Prometheus to track network traffic, node health and blockchain performance metrics. Designed and integrated decentralized storage solutions using IPFS and libtorrent, enabling reliable distributed file management and efficient data availability within the blockchain ecosystem. Developed and enhanced the Smart Contract Virtual Machine (VM) using Rust, WebAssembly (Wasm), and gRPC, enabling secure and efficient smart contract execution. Implemented a stateless VM architecture and integrated blockchain-native capabilities including IPFS-based storage and NFT functionality into smart contracts. Collaborated with the research teams to integrate Proof of Execution using Zero-Knowledge Proofs into the VM state transition model, improving smart contract execution privacy and verification security. Provided technical support and architectural guidance for the development of the Cross-chain decentralized exchange (DEX) deployed on the Sirius Chain smart contracts.

Developed and tested mobile and kiosk gaming applications using Java and Kotlin, contributing to feature improvements and enhanced user experience. Designed and executed black-box testing workflows to validate application functionality, usability, and reliability. Set up and maintained testing environments for mobile and kiosk platforms, supporting efficient QA processes and defect identification. Collaborated with the developers and QA engineers to debug issues, verify fixes, and improve overall software quality.