Team Lead Full-Stack Engineer (f/m/x) in Berlin

As the Team Lead for the backend, frontend, mobile and fullstack software engineers, you will own and shape the architecture of the underlying services as well as their technical roadmap for the services that together create Treeline, our application that helps predict and prevent wildfires, storm events and generally power and train outages due to vegetation, weather and climate.

Technically, that means rendering and querying large volumes of geospatial data efficiently in both browser, mobile and backend, handling complex and custom business logic, writing the services that make that fast, and building integrations for the growing number of third-party consumers of our services.

We are a team of five engineers today, actively growing, embedded in a cross-functional group of product managers, UX/UI designers, data, DevOps, ML, and geospatial engineering experts. You will not be the only person responsible for any system you touch and we’re a friendly bunch.

• Lead, support and coordinate the team that builds Treeline while still being around 60% hands-on
• Architect, build and extend features end-to-end that handle large volumes of geospatial data, with attention to UX and design
• Design and build well-designed, performant API endpoints and backend services used by partners and customers
• Coordinate tightly with other functions in cross-functional temporary squads
• Shape and influence how your team works and how we work together in a greater context

Stack:

• Frontend: React, TypeScript
• Backend: NestJS, TypeORM
• Mobile: React Native
• Database: PostgreSQL (including geospatial workloads, PostGIS and OGC)
• Infrastructure & CI/CD: AWS, GitLab

Must have

• First experience as a team lead, knowing that the team and product takes priority over your own hands-on work, always
• Strong Backend experience with NestJS, Express, or Node.js
• High level of TypeScript, React in production (Vue or Preact also fine — we care that you know a component model well, not which one)
• You've worked in a codebase with CI/CD and code review, and can find your way around a system you didn't build
• You've used AI-assisted coding in your actual day-to-day, not just tried it once

Nice to have

• Spec-driven or test-driven development, agentic or otherwise
• Web-based geospatial / GIS work
• Familiarity with mobile development, especially React Native
• An eye for design and UX — enough to make small design calls without needing a mockup for everything

• The opportunity to create a product that can improve business processes and lives across the globe.
• Flexible working hours and hybrid work model - we trust our employees to get their work done while maintaining a healthy work-life balance.
• We empower employees to drive their own career development, take initiative and have the freedom to be creative and bold.
• Not an overtime culture - we take care that overtime is done only as a necessity and always offset with time off and rest.
• A collaborative and learning environment - frequent internal workshops, knowledge sharing sessions, journal clubs and hackathons.
• Office located in the centre of Berlin Kreuzberg with free fruit, nuts and drinks.
• Potential to participate in the employee stock option program.
• Urban Sports membership and BVG subsidy, corporate pension program.
• A diverse and vibrant international environment of 30+ different nationalities.