Senior Full-Stack Engineer (Go & TypeScript) - Long-Term - Independent Talent Only, No Agencies

We are a fast-growing PropTech startup in Germany, digitizing utility metering and heating cost billing for property managers: remote meter reading, data processing and automated billing for residential buildings. We are looking for a true A-player: a senior full-stack engineer for a long-term, full-time collaboration (40+ hours/week), working day-to-day alongside our lead engineer. You will take ownership of substantial parts of our backend and ship features end-to-end. WHAT YOU'LL WORK ON - Backend services and APIs in Go - Frontend and full-stack features in TypeScript (SvelteKit) - Data integrations with industry standards for metering data - Document and PDF generation pipelines for billing - Reliability, performance and clean architecture of a growing platform MUST-HAVES - 5+ years of professional software development experience - Strong full-stack experience with Go and TypeScript - Proven experience designing and writing backends from scratch - Hands-on with message brokers, PostgreSQL and object storage (S3-compatible) - Independent, reliable, clear communication in English, high ownership NICE TO HAVE - Experience with IoT / metering data, billing systems or document pipelines - Experience in early-stage startups PROCESS Shortlisted candidates will have a technical interview with our lead engineer. Please include links to relevant projects or code samples and briefly describe one backend system you designed yourself. IMPORTANT - Independent freelancers only. No agencies, no exceptions. Agency proposals will be declined. - All communication goes through Upwork. Anyone who contacts our founders or team members directly (by email, LinkedIn, phone or any other platform) will be blocked and excluded from the process.