Jack Zhang (Yingfeng Zhang)

Architected and deployed a vintage poker blockchain game using a hybrid on-chain/off-chain architecture: high-frequency game logic runs off-chain for performance, while settlement, NFT minting, and key state are handled on-chain. Developed ERC20 and ERC721 smart contracts with Solidity, using Foundry, Hardhat, and Remix for development, testing, and deployment; gained hands-on experience across TRON, Sepolia, Conflux, NEO, and 0G. Focused on smart contract quality and code standards: used OpenZeppelin libraries and designed tests around access control, signature flows, common risks, duplicate submissions, and state consistency. Extended the project to the 0G EVM chain during a hackathon: designed a dual-chain factory model and settlement router for TRON/0G switching; deployed ERC-7857 Interactive NFT contracts on 0G and integrated decentralized storage plus Data Availability for verifiable fairness. Designed delegated signature flow for gas-free user experience; implemented AMM market-making logic and DAO governance functions for the in-game token economy. Built the full-stack DApp with Socket.io real-time communication, implemented on-chain/off-chain event state synchronization, and added end-to-end automated testing for deployment and regression validation. Continuously follow Solidity, EVM, DeFi, Layer2, Oracle, cross-chain, and smart contract engineering best practices, with ability to learn new protocols quickly and apply them in real projects. Built a Vue + PHP + Stripe transaction platform; developed a mahjong tile recognition AI with TensorFlow/PyTorch, participated in AWS project development, combining full-stack and AI toolchain experience.

Led architecture design and implementation of the OpenHarmony AGP 3D rendering engine and physics engine, with deep experience in complex low-level systems engineering. Led critical performance optimizations including camera transitions, HDR activation, pipeline preloading, and texture resolution optimization, reducing power consumption by 30%. Built and led 4 teams across app and rendering domains, collaborating with Turkey and Netherlands R&D centers and driving cross-team delivery. Launched Huawei Maps international version from scratch with 50+ major features and maintained 99.9% stability with crash rate below 0.1%. Designed device/cloud rendering architecture and LOD tile rendering, reducing traffic by 20%+ and power consumption by 10%+; this experience maps well to reliability and performance optimization in hybrid on-chain/off-chain systems.

Built the Maps SDK team from zero, recruiting 20 engineers across basemap, rendering, iOS, Android, and web. Led full migration from Tencent Maps to a self-developed rendering engine, covering basemap data conversion, compilation, backend download services, vector/raster tile production, and rendering. Improved nationwide data compilation efficiency from 24 hours to 3 hours through pipeline optimization, with strong experience in automation tooling and engineering efficiency. Led development of WebGL basemap, WYSIWYG style editor, navigation replay system, and automated testing platform; owned complex debugging and high-stability delivery.

Tencent Maps core development: led iOS 3D engine migration, street view maps, animation framework, and OpenGL shader refactoring; participated in POI search, route planning, and offline map architecture redesign. Cross-platform system lead: founded a cross-platform team and introduced OpenGL into the system, enabling one codebase to run across Symbian, MTK, Android, iOS, and other platforms. Developed a 3D page-turning algorithm for QQ Reader and WeChat Reader; patent granted. Served as core developer for QQ Music.