Full-Stack Javascript Engineer

ppYopeso has been developing a diverse range of software products, from large-scale applications to smaller solutions, for 20 years./p pWith a growing team of over 300 employees across five locations, we are dedicated to fostering a culture of growth, transparency, and professionalism./p pAt Yopeso, we value authenticity, curiosity, and ambition.These values drive us to build strong connections within our community and with our partners, ensuring trust, integrity, and transparency in all our business practices.We strive to maintain the highest professional standards and continuously challenge ourselves to develop high-quality, high-performance, and secure software solutions./p pOur approach is rooted in efficient collaboration among passionate professionals working in agile teams.Guided by curiosity and ambition, we strive to create products that are meaningful and impactful, while remaining true to our authentic selves./p pWe are seeking an experienced Full Stack Developer to join our team working on an open-source AI chat platform.The successful candidate will contribute to developing and maintaining a sophisticated conversational AI application that integrates multiple AI providers and offers a rich user experience, while collaborating closely with product and design stakeholders./p h3Key Responsibilities /h3 ul liDevelop and maintain both frontend and backend components of the AI chat platform /li liImplement new AI provider integrations and chat functionalities /li liWork with modern React-based frontend and Node.js/Express backend architecture /li liCollaborate on database design and optimization using MongoDB /li liImplement and maintain real-time features using WebSocket connections /li liWrite comprehensive tests and ensure code quality through automated testing /li liDeploy and maintain containerized applications using Docker /li liParticipate in code reviews and maintain high development standards /li /ul h3Required Technical Skills /h3 h3Frontend Development /h3 ul liReact.js (v18+) with modern hooks and functional components /li liTypeScript for type-safe development /li liVite for build tooling and development server /li liTailwindCSS for styling and responsive design /li liRadix UI and Headless UI for accessible component libraries /li liTanstack Query (React Query) for data fetching and state management /li liReact Router for client-side routing /li liState management with modern React patterns /li /ul h3Backend Development /h3 ul liNode.js (v18+) with Express.js framework /li liMongoDB with Mongoose ODM for database operations /li liPostgreSQL structured data storage /li liRedis for caching and session management /li liRESTful API design and implementation /li liJWT and session-based authentication /li /ul h3DevOps Infrastructure /h3 ul liDocker and Docker Compose for containerization /li liMongoDB database administration /li liEnvironment configuration and secrets management /li /ul h3Development Tools /h3 ul liGit with advanced workflows (rebasing, merging, conflict resolution) /li liESLint and Prettier for code quality /li /ul h3Required Experience /h3 ul li3+ years of full-stack JavaScript/TypeScript development /li liFluent in English, both written and verbal /liliExcellent communication and collaboration skills /li liAbility to work independently and manage complex projects /li /ul h3Nice to Have /h3 ul liExperience with OpenAI API, Anthropic Claude, or similar LLM APIs /li liUnderstanding of prompt engineering and AI model integration /li liLangChain framework for AI application development /li liRAG (Retrieval-Augmented Generation) implementation experience /li /ul h3Work Arrangement /h3 pAvailability to work on-site from our Madrid office a few days per week, with the rest of the time remote./p /p #J-*****-Ljbffr

p h3Key Responsibilities /h3 ul liDevelop and maintain both frontend and backend components of the AI chat platform /li liImplement new AI provider integrations and chat functionalities /li liWork with modern React-based frontend and Node.js/Express backend architecture /li liCollaborate on database design and optimization using MongoDB /li liImplement and maintain real-time features using WebSocket connections /li liWrite comprehensive tests and ensure code quality through automated testing /li liDeploy and maintain containerized applications using Docker /li liParticipate in code reviews and maintain high development standards /li /ul h3Required Technical Skills /h3 h3Frontend Development /h3 ul liReact.js (v18+) with modern hooks and functional components /li liTypeScript for type-safe development /li liVite for build tooling and development server /li liTailwindCSS for styling and responsive design /li liRadix UI and Headless UI for accessible component libraries /li liTanstack Query (React Query) for data fetching and state management /li liReact Router for client-side routing /li liState management with modern React patterns /li /ul h3Backend Development /h3 ul liNode.js (v18+) with Express.js framework /li liMongoDB with Mongoose ODM for database operations /li liPostgreSQL structured data storage /li liRedis for caching and session management /li liRESTful API design and implementation /li liJWT and session-based authentication /li /ul h3DevOps Infrastructure /h3 ul liDocker and Docker Compose for containerization /li liMongoDB database administration /li liEnvironment configuration and secrets management /li /ul h3Development Tools /h3 ul liGit with advanced workflows (rebasing, merging, conflict resolution) /li liESLint and Prettier for code quality /li /ul h3Required Experience /h3 ul li3+ years of full-stack JavaScript/TypeScript development /li liFluent in English, both written and verbal /liliExcellent communication and collaboration skills /li liAbility to work independently and manage complex projects /li /ul h3Nice to Have /h3 ul liExperience with OpenAI API, Anthropic Claude, or similar LLM APIs /li liUnderstanding of prompt engineering and AI model integration /li liLangChain framework for AI application development /li liRAG (Retrieval-Augmented Generation) implementation experience /li /ul h3Work Arrangement /h3 pAvailability to work on-site from our Madrid office a few days per week, with the rest of the time remote.

ppYopeso has been developing a diverse range of software products, from large-scale applications to smaller solutions, for 20 years. /p pWith a growing team of over 300 employees across five locations, we are dedicated to fostering a culture of growth, transparency, and professionalism. /p pAt Yopeso, we value authenticity, curiosity, and ambition. These values drive us to build strong connections within our community and with our partners, ensuring trust, integrity, and transparency in all our business practices. We strive to maintain the highest professional standards and continuously challenge ourselves to develop high-quality, high-performance, and secure software solutions. /p pOur approach is rooted in efficient collaboration among passionate professionals working in agile teams. Guided by curiosity and ambition, we strive to create products that are meaningful and impactful, while remaining true to our authentic selves. /p pWe are seeking an experienced Full Stack Developer to join our team working on an open-source AI chat platform.