Senior Full-stack Engineer (backend-leaning)

Hi there :) Thanks for checking in to find out about our open position. We´ll provide as much information as possible, but please feel free to reach us if you have further questions. We´ll be happy to see your application, even if there are skills you don't quite master! ABOUT US At South Geeks, we connect top LATAM engineering talent with innovative companies building impactful products worldwide. We focus on long-term partnerships, strong technical environments, and creating spaces where professionals can grow, contribute, and thrive. ABOUT THE CLIENT Our client is a health tech startup redefining medical device innovation with an AI platform that automates research, documentation, and workflows end-to-end, helping deliver lifesaving devices sooner. The product combines customer onboarding flows, a Neo4j knowledge graph and an AI/LLM-powered recommendation and scoring system, with applicability in regulated environments such as medical device, pharma, and parametric documentation. ABOUT THE ROLE We are looking for a Senior Full-Stack Engineer (backend-leaning) with 6 to 10 years of experience who can translate conceptual product ideas into solid, shippable code. You will work directly with the Product team on daily scoping and end-of-day mini demos and collaborate with the fractional CTO on architectural decisions. Roughly 70% of your time will go to new feature development and enhancements and the remaining 30% to resolving customer-reported bugs. You will have real influence on technical decisions and are expected to bring informed opinions on trade-offs. WHAT YOU NEED TO SUCCEED IN THIS ROLE - 6 to 10 years of professional software engineering experience - Strong Python and JavaScript/TypeScript - React on the frontend - Neo4j (graph database) experience - GraphQL - Production-level AI/LLM integration experience (beyond basic prompting) - Experience working with or building MCP servers - 100% Eastern Time overlap during business hours - Excellent written and sp