Full-Stack Engineer (React.js, Node.js, AI Integrations)

Kilona.io is building an AI-powered web application to help researchers and medical professionals explore and analyze medical research papers. We are looking for an experienced Full-Stack Engineer to help scale and evolve this actively developed platform.

• Develop and maintain a web application using React.js
• Build and optimize backend services with Node.js
• Integrate AI services (OpenAI and similar models) for document analysis and research workflows
• Work with structured and unstructured data (PDFs, text, metadata)
• Collaborate closely with product, AI, and design stakeholders
• Improve performance, code quality, and system reliability
• Participate in architectural decisions and feature planning

• 2.5+ years of commercial experience with React.js
• Strong backend experience with Node.js
• Solid understanding of modern JavaScript (ES6+)
• Experience integrating AI APIs (OpenAI, LLM-based services, embeddings, etc.)
• Experience working with REST APIs and databases
• Good understanding of async workflows and data-heavy applications
• Confident spoken English for international team communication
• Nice to Have: LangGraph / agent-based AI workflows, AI-powered search, RAG systems, document processing experience, Polish language, experience with scientific/medical/research products

• Fully remote
• Flexible working hours with reasonable team overlap
• Long-term project with real product impact
• Collaborative, no-bureaucracy environment
• Opportunity to work deeply with AI-driven features, not just API wrappers