Senior Engineer needed for decentralized E-Commerce Platform

Job Description: We are building a decentralized e-commerce marketplace where users can buy products and services with cryptocurrency, complete blockchain-based payments, and use decentralized infrastructure for data and digital asset storage. This is a real-world Web3 product, not a concept or proof-of-concept. We are looking for a hands-on full-stack engineer who has integrated blockchain functionality into shipped products. Side projects alone are not sufficient; we want someone who has delivered production or production-like Web3 applications and can explain the architecture decisions behind them. Scope of Work: - Build core marketplace functionality: listings, carts, user accounts, and order management. - Implement crypto payments with wallet-based transactions and on-chain verification. - Develop smart contracts for payment processing, settlement, and marketplace operations. - Integrate decentralized storage for product metadata, digital assets, and application content using IPFS, Filecoin, or Arweave. - Build a responsive marketplace frontend with wallet connectivity. - Develop backend APIs, blockchain event listeners, transaction monitoring, and asynchronous processing. - Support end-to-end testing, documentation, and deployment instructions. Required Technical Experience: - Solidity on an EVM chain such as Ethereum, Polygon, or Base. - Web3.js or Ethers.js, including contract deployment, testing, and integration. - Crypto payment integrations and wallet connectivity. - Frontend: React or Next.js with TypeScript, MetaMask and/or WalletConnect. - Backend: Node.js with Express or NestJS, REST APIs, blockchain event listeners, PostgreSQL or MongoDB. - Decentralized storage: content addressing, data retrieval, and clear understanding of the on-chain vs. off-chain split. - Transaction monitoring and asynchronous processing. Deliverables: - Working frontend marketplace UI. - Wallet and crypto payment flow. - Marketplace smart contracts. Decentralized storage integration. - Backend APIs and transaction monitoring. - End-to-end testing. - Documentation and deployment instructions. Ideal Candidate: You have previously built a Web3 marketplace, dapp, or crypto payment system. You can clearly explain why you made specific architecture calls, including what belongs on-chain versus off-chain, how payment verification and settlement are handled, and how decentralized storage is integrated into the product. To Apply: Please send: - GitHub repositories or past project links. - A short note on your experience with blockchain payments and decentralized storage. - A brief explanation of a relevant architecture decision you made and why. - Real shipped work is more important than a resume. - Engagement structure and milestones can be discussed based on your experience.