Senior Backend Engineer (f/m/x) – API & Platform

Intro Hamburg Hybrid (2–3 days/week onsite) | 70.000 - 85.000 € p.a. (40 hrs / full time) | 30 Days Vacation | English B2 | German C1 Are you passionate about building the technical backbone of the energy transition? Join suena energy as Senior Backend Engineer (f/m/x) and become a founding member of our newly formed Platform team. You'll help design and build the API and integration layer that connects our trading, analytics, and optimization systems — and in doing so, directly shape how clean energy is managed across European power markets. suena energy is a green tech startup specializing in algorithmic energy trading for battery storage systems and renewables. Our vision: a world where clean energy is used reliably, economically, and intelligently. With our AI-based optimization and trading software, we maximize the revenues of operators of large-scale energy storage and renewable assets on short-term electricity and balancing markets - while simultaneously minimizing their risks. We're a team of 50+ people, combining a warm, supportive culture with real startup drive. Following our successful Series A, we're now building a dedicated Platform team from scratch. Quick Check: Is this your kind of engineering challenge? Tech Stack: Python (Django/FastAPI), PostgreSQL/TimescaleDB, Redis, Celery, Docker, AWS, GitLab CI/CD, Sentry, Grafana Your Focus: API design hands-on experience with PostgreSQL/TimescaleDB is a plus Experience with distributed/cloud-based architectures (AWS preferred), Docker, CI/CD, async workflows (Celery, Redis) You think beyond the ticket — you understand how systems connect and can make principled architecture decisions Security-minded: authentication, authorization, zero-downtime deployments are familiar territory Comfortable working across greenfield projects and legacy systems German C1 is required for this role — we work closely with German-speaking external API partners and system integrators, and clear, direct communication in German is essential for this English B2/C1 for internal collaboration Nice to have: Experience or genuine curiosity about energy markets, trading systems, or related domains (finance, IoT). The domain is complex — enthusiasm to learn it matters. Why us? Shape the Future: Contribute to the energy transition by working on sustainable energy solutions in a growing market environment. Connecting