Senior Software Engineer (Backend) (m/w/d)

Lumenaza GmbH; Berlin; Hybrid; EUR 90.000 - 120.000; Vollzeit

Benefits dieser Stelle

Competitive compensation

Flexibility in hours and hybrid work setup

Structured onboarding and continuous learning

Impactful work on renewable energy projects

Zusammenfassung

A green-tech company in Berlin is seeking a Senior Backend Engineer to design and implement scalable backend systems for the decentralized energy sector. You will work on core systems for billing and market processes while leading architectural decisions and collaborating with cross-functional teams. Ideal candidates should have over 5 years of backend experience, strong expertise in Python and Django, and the ability to solve technical challenges. The role offers flexibility and growth opportunities in a modern work environment.

Qualifikationen

• 5+ years of backend development experience.
• Strong expertise in Python and Django.
• Experience in designing and building REST APIs.
• Familiarity with distributed systems and microservices.
• Solid understanding of databases, especially PostgreSQL.
• Experience with Docker and CI/CD workflows.
• Strong communication skills in English.

Aufgaben

• Design and implement scalable backend systems for billing and energy processes.
• Work across the full lifecycle from design to deployment.
• Develop robust solutions involving data modeling and asynchronous processing.
• Collaborate closely with Product, Frontend, and DevOps teams.
• Drive improvement and innovation in engineering practices.
• Modernize and migrate legacy systems toward modern architectures.

Kenntnisse

Backend development experience

Python

Django

REST APIs

Distributed systems

PostgreSQL

Docker

CI/CD workflows

Strong communication skills in English

Tools

Django REST Framework

Kubernetes

Redis

Celery

GitLab CI/CD

Robot Framework

React

Jobbeschreibung

This is us

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 tasks

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 You’ll 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.

Your profile

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

Our Tech Stack

• 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.

Your team

We offer you this

• 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.

Apply now!