Senior Backend Engineer - API & Platform

• Tech Stack: Python (Django/FastAPI), PostgreSQL/TimescaleDB, Redis, Celery, Docker, AWS, GitLab CI/CD, Sentry, Grafana
• Your Focus: API design & architecture, backend integrations, data flows, system reliability and scalability
• Team: Small, newly formed platform squad - you’ll work closely with the Platform Lead, with strong support from our CTO in the early phase
• Product: Real-time energy trading platform - high complexity, data-heavy, ML-integrated
• Who thrives here: Engineers who think in systems, take ownership, and are energized by building things that actually matter
• Must-haves: 5+ years backend experience, solid API & architecture background, Python, cloud deployment, German C1
• Dealbreakers: No API/architecture experience, pure CRUD background, no interest in complex distributed systems

Your mission

• Design and build scalable, reliable APIs and backend integrations that connect trading, analytics, data science, and forecasting systems
• Drive the architecture of suena’s platform layer - from initial design decisions to production
• Own data flows and backend automations across the platform
• Collaborate closely with the Platform Lead, CTO, and cross-functional teams (trading, data science, modelling) to translate complex domain requirements into robust technical solutions
• Improve and extend existing systems while keeping a clear eye on reliability, security, and performance
• Contribute to technical standards, code reviews, and engineering practices as the team grows, * People at the Core: Clear structures, democratic decisions, and a feedback culture where your voice counts.
• Shape the Future: Contribute to the energy transition by working on sustainable energy solutions in a growing market environment.
• Connecting & Co-Creating: Strategy off-sites and onsite weeks for real collaboration and shared ideas.
• Work Your Way: Home office and flexible hours - you know what works best for you and your team.
• Good Vibes: Yoga, shared lunches, after-work fun - we keep the energy up, even when it’s busy.
• Body & Mind: Urban Sports Club or Wellpass - your choice. Plus wellbeing check-ins and mental health support via nilo.health - your energy matters.
• New Office: 10th-floor office with rooftop terrace, canteen, great views, ergonomic desks, hardware of your choice, and a pet-friendly environment.
• Sustainable Extras: Subsidized Deutschlandticket, JobRad, Givve Card and more - supporting your mobility and everyday life.

What else?

A note on applications

As part of your application, we’d love to see a Python project you’re genuinely proud of - production code, a side project, a study case, anything goes. It doesn’t need to be polished. We’ll use it as the basis for a technical conversation: what decisions did you make, why, what would you do differently? Send us the link of your repository. Be sure we have access.

If you don’t have something ready to share, no problem - we’ll send you a small, focused task instead.

Not quite senior level yet, but this role sounds like the direction you’re heading? Apply anyway and let us know - we’re also building out the junior side of the team.

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., * 5+ years of backend engineering experience, with a strong focus on API design and system architecture

• Solid Python skills (Django and/or FastAPI); 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.

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.

suena energy is a green tech startup specializing in algorithmic energy trading for energy storage systems and renewables. Our vision: a world where clean energy is used reliably, economically, and intelligently-and where we actively accelerate the energy transition by enabling batteries and renewables to power our grids. With our AI-based optimization and trading software, we maximize the value and market participation of large-scale energy storage and renewable assets in short-term electricity and balancing markets-while minimizing risk for operators.

We’re a 50+ person team that’s fast-paced by nature, but the kind of place where people actually look out for each other. Following our successful Series A, we’re on a strong growth trajectory and continue to expand-impacting the future of energy together every day. At suena, you’ll find the freedom to shape your work, bring your ideas to life, and help accelerate the energy transition as part of a passionate, cross-functional team.

Ready to make a difference? Find your next challenge with us!

https://www.youtube.com/watch?v=-Dsctj9qh2s