About Aetium Aetium is a climate-tech company and We are building the future of sustainable mobility platform called "EcoWheel". We help reduce carbon emissions through an e-bike rental platform powered by blockchain and AI. Our platform includes: E-bike rental marketplace Fleet management CO₂ Token Layer Carbon marketplace AI-powered features About the Role We are looking for a Senior Full Stack Engineer with experience in React, NestJS, and Solidity to help build and improve the EcoWheel platform. You will work on both the frontend and backend, develop smart contracts, and build scalable features for our climate-tech platform. Responsibilities Develop web applications using React and TypeScript. Build REST APIs with NestJS. Design and maintain PostgreSQL databases. Develop Solidity smart contracts. Integrate blockchain features and wallet authentication. Build the CO₂ Token Layer. Write clean, maintainable, and well-tested code. Collaborate with designers and other engineers. Requirements 5+ years of software development experience. Strong React and TypeScript skills. Strong NestJS and Node.js experience. Experience with PostgreSQL. Experience developing Solidity smart contracts. Knowledge of Ethereum or Arbitrum. Nice to Have OpenZeppelin Hardhat or Foundry AI integrations Marketplace or SaaS experience Technology Stack React TypeScript NestJS Node.js PostgreSQL Solidity Ethereum Arbitrum ERC-20 / ERC-721 / ERC-1155 Ethers.js or Viem Google Maps API Docker GitHub What We Offer Fully remote Flexible working hours 20–30 hours per week Long-term collaboration Competitive hourly rate based on experience You can check here more details How to Apply If you're interested in joining the EcoWheel team, we'd love to hear from you. Please update following. Your resume (CV) GitHub profile Portfolio or LinkedIn profile (optional)