Senior Software Engineer (Backend) (mwd)

Lumenaza is a green-tech company building software for the decentralized energy world. Our platform enables energy providers to manage billing market communication and energy data supporting renewable energy business models at scale.

We are driven by a clear mission: accelerating the transition to a sustainable energy system. At the same time we value diversity collaboration and continuous learning.

Your Role

As a Senior Backend Engineer you will design and build core systems that power real-world energy processes from billing to market communication.

You take ownership of complex domains contribute to architectural decisions and help evolve both our systems and engineering practices.

What Youll Do

• Build and own core backend systems
  Design and implement scalable solutions for billing tariff models and energy market processes.

• Shape system architecture
  Work across the full lifecycle from design to deployment ensuring maintainability scalability and correctness.

• Solve complex technical challenges
  Develop robust solutions involving data modeling asynchronous processing and distributed systems.

• Collaborate across disciplines
  Work closely with Product Frontend and DevOps to deliver cloud-based solutions and improve our platform.

• Drive improvement and innovation
  Bring in new ideas improve engineering practices and explore modern development approaches including AI-assisted workflows.

• Modernize existing systems
  Help evolve and migrate legacy systems toward modern architectures.

Core Requirements

• 5 years of backend development experience

• Strong Python and Django expertise

• Experience designing and building REST APIs

• Experience with distributed systems / microservices

• Solid understanding of databases (PostgreSQL)

• Experience with Docker and CI/CD workflows

• Strong communication skills in English

Nice to Have

• Experience with FastAPI Pydantic or Django Ninja

• Knowledge of Celery or similar async tools

• Experience integrating external systems (e.g. ERP APIs)

• Familiarity with React / TypeScript

• Interest in energy markets or regulated domains

• Python Django Django REST Framework

• PostgreSQL Redis

• Celery (async processing)

• Docker Kubernetes

• GitLab CI/CD

• Robot Framework (testing)

• React (frontend)

We deploy continuously to Kubernetes and work with distributed systems handling complex business-critical data.

• Impact: Build software that directly enables renewable energy business models

• Ownership: Work on complex meaningful systems with real-world impact

• Growth: Structured onboarding and continuous learning

• Flexibility: Flexible hours and hybrid work setup

• Benefits: Competitive compensation Deutschlandticket

• Location: Modern office in Berlin Kreuzberg

We strongly encourage applications from underrepresented groups in tech and are committed to building an inclusive environment.