Backend & Infrastructure Engineer

About the Role

This is a rare opportunity to own the entire backend and infrastructure of a physics-based simulation platform used for large-scale commercial battery storage projects. The software helps installers, wholesalers, and distributors size, simulate, and sell battery projects — replacing manual spreadsheet work with data-driven, simulation-backed proposals in minutes.

Each simulation compares hundreds of battery variants across multiple stacked application scenarios (peak shaving, arbitrage, grid services, and more), producing millions of data points. Compute scales on three axes simultaneously: more users, more usage per user, and increasingly complex simulations. You'll be the engineer who ensures the backend can support a 100x growth in customer base
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The platform currently operates across six European countries in a market that is doubling year over year. The stakes are high — simulation results guide 6–8 figure investment decisions.

• Own the full backend and infrastructure stack end-to-end, from service reliability and security to performance and cost control.

• Architect and scale systems to handle rapidly growing, compute-heavy simulation workloads.

• Manage and improve containerised infrastructure, orchestration, job queues, and monitoring.

• Make high-impact architectural decisions — including whether the current Python engine should be partially or fully rewritten in another language.

• Continuously improve the simulation engine's capabilities to support new battery application scenarios and market environments.

• Harden production systems for reliability and security as the customer base grows.

• Optimise backend performance and manage compute costs at scale.

• Work closely with a small, fast-moving team that prioritises shipping speed and product quality.

Must-have:

• 5+ years of experience owning and scaling production backend systems under real-world load.

• Hands-on expertise with web application infrastructure scaling: containers, orchestration, queues, monitoring, performance optimisation, and cost control.

• Proficiency in Python, or strong willingness to work in Python while driving architectural decisions about potential rewrites.

• Proven ability to design and implement backend architectures for compute-heavy, scaling applications.

• Comfort making sound architectural decisions with incomplete information.

• Experience with service reliability, security hardening, and production monitoring.

• Track record of working independently and owning projects end-to-end.

• Prior experience in early-stage startup environments with rapid iteration cycles.

• Pragmatic engineering mindset: you know when to optimise, when not to, and when a simple solution beats a sophisticated one.

• AI tools are embedded in your development workflow — and you can still debug independently when they fall short.

Nice to have:

• Experience with physics simulations or numerical computing workloads.

• Background in energy markets, electrical engineering, or energy management systems.

• Base salary: €110,000 – €150,000 per year

• Equity: 0.5% – 2.5%, with standard 4-year vesting and 1-year cliff

Based in Berlin, Germany
. The role is on-site or hybrid. Remote-only candidates are not considered at this time.

The interview process consists of 1–2 conversations plus a technical assessment on a real project.