Freelance Full-Stack Web App Developer

Mindrift is looking for skilled Full-Stack Web App Developers (JavaScript/TypeScript + Python or Node) to join the Tendem project (https://tendem.ai/) and build interactive browser-based applications for real-world use cases. In this role, you'll apply your full-stack engineering expertise to design, build, and maintain functional, robust, and user-friendly web applications. This part-time remote opportunity is ideal for professionals with hands-on experience in modern frontend frameworks, backend APIs, databases, and shipping interactive web products end-to-end. What We Do The Mindrift platform connects specialists with innovative technology projects. Our mission is to help develop high-quality AI technologies by combining real-world expertise from professionals across the globe with advanced AI development efforts. About The Role This is a freelance role for a Tendem project. As a Full-Stack Web App Developer, you'll design, build, and refine browser-based applications with real logic, state, persistence, and user input — from habit trackers and budgeting tools to internal dashboards, mini-SaaS tools, and AI-powered apps. You may also work on standalone Python applications and data-processing scripts that sit alongside or behind these products. Key Responsibilities • Build interactive web applications with frontend (React, Next.js, Vue, or similar) and a backend API (Python/FastAPI/Flask or Node/Express) • Design and implement data models, schemas, and persistence layers using SQL (PostgreSQL, SQLite) or NoSQL stores • Implement authentication, sessions, and basic role-based access where needed • Integrate third-party APIs and AI/LLM services (OpenAI, Anthropic, or similar) into product features • Handle state management, user input validation, error states, and loading states cleanly • Build standalone Python tools and scripts where required by the task (data processing, API clients, lightweight backend utilities) • Review, debug, optimize, and refactor full-stack applications to improve correctness, security, performance, and maintainability • Write clear, testable code and debug end-to-end issues across frontend, backend, and database Educational Qualifications • At least 3 years of relevant experience in full-stack web development or shipping interactive web applications (required) • Bachelor's or Master's Degree in Computer Science, Engineering, Information Technology, or related technical fields is a plus Academic and/or Professional Experience Candidates should have a strong foundation in full-stack web development, modern frontend frameworks, backend architecture, and building interactive browser-based applications end-to-end. We are looking for specialists who can confidently work across frontend, backend, databases, and APIs, design robust application logic, and build production-ready web applications. Strong problem-solving skills, attention to detail, and the ability to independently architect and ship complete features are essential. Technical Skills (Essential) • Strong command of JavaScript/TypeScript and at least one modern frontend framework (React, Next.js, Vue, Svelte, or similar) • Solid backend experience in Python (FastAPI, Flask, Django) and/or Node.js (Express, NestJS) • Hands-on experience with relational databases (PostgreSQL, MySQL, SQLite) and basic schema design • Experience implementing REST APIs, request validation, error handling, and authentication flows • Familiarity with deployment platforms (Vercel, Netlify, Render, Fly.io, Railway, or similar) • Experience integrating LLM APIs or other AI services into product features is a strong plus • Comfortable with version control (Git) and basic testing practices Additional Requirements • Strong attention to detail and commitment to building working, robust products — not demos • Self-directed work ethic with the ability to architect, build, and ship features independently • Portfolio of shipped web applications (required) • English