Software Developer

Frontend Developer Responsibilities:
- Build marketplace UI, including loading states, empty states, error handling, and wallet connection flows.
- Develop course card components, including visual polish, wishlist toggles, and responsive layouts.
- Integrate MetaMask, including wallet connect/disconnect states, wrong-network warnings, and transaction feedback.
- Improve accessibility, including navigation landmarks, focus management, ARIA attributes, and keyboard navigation.
- Perform frontend testing, including unit and integration tests for key user flows.

Frontend Developer Qualifications:
- Strong experience with React and Next.js (Pages Router).
- Experience building wallet connection flows with MetaMask or similar Web3 wallets.
- Solid understanding of component-level state management and async data handling.
- Experience with Tailwind CSS and responsive design.
- Familiarity with frontend testing tools like Jest or React Testing Library.
- Ability to explain changes in plain language to a non-technical project owner.

Backend Developer Responsibilities:
- Harden APIs, including Ethereum address validation, request validation, and consistent error responses.
- Implement rate limiting, including per-IP throttling for API endpoints.
- Ensure concurrent write safety to prevent data corruption on simultaneous requests.
- Develop an analytics endpoint to aggregate data from multiple sources with caching.
- Create shared API utilities, including reusable helpers for error handling, validation, and method checks.
- Execute database migration from JSON file storage to PostgreSQL.

Backend Developer Qualifications:
- Strong experience with Node.js and REST API development.
- Experience with input validation and API security best practices.
- Understanding of concurrent write safety and race condition prevention.
- Experience with PostgreSQL or similar relational databases.
- Familiarity with Next.js API routes or Express.js.
- Ability to demonstrate backend changes to a non-technical project owner.

Solidity Smart Contract Developer Responsibilities:
- Implement price floor guards, including owner-settable minimum course prices with custom errors.
- Develop batch operations for atomic batch activation in admin course management.
- Conduct comprehensive testing for authentication checks, edge cases, revert conditions, and event emissions.
- Prepare security documentation, including threat analysis, refund safety reviews, and gas optimization notes.
- Handle on-chain verification, including deploying, testing, and verifying changes through the frontend.

Solidity Smart Contract Developer Qualifications:
- Strong experience with Solidity (0.8.x).
- Experience writing and deploying smart contracts on Ethereum or EVM-compatible chains.
- Solid understanding of security patterns, including Checks-Effects-Interactions, reentrancy prevention, and access control.
- Experience with Truffle or Hardhat for development and testing.
- Experience writing comprehensive smart contract tests using Mocha or Chai.
- Ability to explain contract changes in plain language to a non-technical project owner.

Location: Remote - Anywhere

Skills required for this job:

• API Security
• Back-end development
• Ethereum
• Front-end development
• Front-end testing
• Next.js
• Node.js
• PostgreSQL
• REST API
• React.js
• Responsive web design
• Smart contract
• Smart contract testing
• Solidity
• Solidity smart contract audit
• Solidity smart contract development
• Tailwind.css
• Web3 development