Web3.js Developer

You will lead and own backend development using Node.js and Express.js. You will design, build, and maintain scalable RESTful APIs and microservices architecture. Additionally, you will write, debug, and optimize complex raw SQL queries for performance and scalability. Your responsibilities will also include working with PostgreSQL and Sequelize ORM for data modeling and management. You will implement caching solutions using Redis and integrate real-time features using Socket.io. Moreover, you will develop and integrate smart contracts (Solidity / Rust) and work with blockchain protocols such as Ethereum, Polygon, BNB Chain, Solana, etc., to enable smooth crypto transactions. Your role will also involve designing and implementing wallet integrations (MetaMask, WalletConnect, custom/custodian wallets) and integrating Web3.js / Ethers.js or similar blockchain libraries into the backend. **Key Responsibilities:** - Lead and own backend development using Node.js and Express.js - Design, build, and maintain scalable RESTful APIs and microservices architecture - Write, debug, and optimize complex raw SQL queries for performance and scalability - Work with PostgreSQL and Sequelize ORM for data modeling and management - Implement caching solutions using Redis - Integrate real-time features using Socket.io - Develop and integrate smart contracts (Solidity / Rust) - Work with multiple blockchain protocols (Ethereum, Polygon, BNB Chain, Solana, etc.) - Design and implement wallet integrations (MetaMask, WalletConnect, custom/custodian wallets) - Integrate Web3.js / Ethers.js or similar blockchain libraries into the backend **Qualifications Required:** - 3-5 years of experience as a Backend Developer with at least 2-3 years working on blockchain projects - Expertise in raw SQL queries, indexing, joins, query tuning, and optimization - Strong proficiency in PostgreSQL and Sequelize ORM - Hands-on experience with Docker, Redis, and Socket.io - Familiarity with AWS cloud services (EC2, S3, RDS) - Strong understanding of backend performance optimization techniques - Proven leadership or mentoring experience in engineering teams - Strong proficiency in Solidity (Rust is a plus) - Experience with Web3.js / Ethers.js or similar blockchain libraries - Experience with multiple blockchain protocols (Ethereum, Polygon, BNB Chain, Solana, etc.) - Knowledge of wallet integrations (MetaMask, WalletConnect, custom/custodian wallets),