(Senior) Software Engineer Data Integration

• Join us fully remote #LI-Remote  or at our lovely office in Cologne in a hybrid working mode
• Option for remote work from abroad (up to three months per year from anywhere in the EU or the USA)
• State of the art technology and modern tech stack
• Excellent hardware equipment (16-inch MacBooks, 2 screens at the office)
• 30 holidays + 3 corporate holidays
• Support for your health through Urban Sports Club cooperation
• Professional mental wellbeing support through our partner nilo for you and your family
• Flexible use of a monthly mobility budget (e.g. Jobrad, public transport)
• Time and resources for individual growth
• Regular tech & growth talks for internal knowledge sharing
• envelio pension plan
• Regular company and team events

Perfection is a myth! We're more interested in the human behind the screen, so think of these criteria as helpful directions — we're excited to see how your unique skills might fit in.

• You have 2+ years of relevant experience in backend development with a focus on data engineering, API integration, or event-driven systems.
• You have a degree in Computer Science, Data Science, Software Engineering, Electrical Engineering, Industrial Engineering, or a comparable field of study.
• You have practical experience in Python programming and are familiar with common best practices.
• You have experience with SQL databases, preferably PostgreSQL or TimescaleDB, in the area of data modelling and query design.
• You have experience integrating with external APIs or streaming systems (e.g. Kafka, MQTT, REST or gRPC).
• Ideally, you are familiar with IoT or energy domain protocols (e.g. MQTT, IEC104) and have worked with real-time data pipelines.
• You are a team player and passionate about working with talented and inspiring people.
• You are looking for technical challenges and pride yourself in finding smart and simple solutions for complex problems.
• You are familiar with parts of our tech stack and are looking forward to keeping up with current industry best practices.
• You are business-fluent in English (Level C1).

As (Senior) Software Engineer Data Integration (all genders), you design innovative software solutions that set our products apart from the masses. Within the Engineering team, you play an important role in further shaping and developing our platform.

With a focus on real-time measurement data and system integration, you are the interface between external source systems — from IoT devices to grid operator APIs — and our Intelligent Grid Platform (IGP). In a dynamic team, you build and evolve the components that bring live measurement data and grid asset information reliably into the IGP.

• You build new measurement integrations end-to-end: connecting external IoT devices (via Kafka, MQTT, IEC104, REST, gRPC) through device registration and normalization to live data ingestion, transformation, and storage.
• You design and improve the measurement integration framework to make adding new sources faster, more reliable, and more observable.
• You own the full integration lifecycle — from raw external data to normalized, mapped measurements, including custom transformations and ID mappings.
• You contribute to the existing ETL framework for importing and digitizing customer grid data from heterogeneous source formats.
• You optimize existing components for performance, reliability, and transparency across batch and streaming workloads.
• You have a continuous improvement mindset and actively look for ways to bring our code to industry best practices with confidence.

• Agile working method with Kanban in interdisciplinary squads.
• Continuous Integration / Continuous Delivery.
• Unit Test mentality and 4-eyes principle during code reviews.
• Knowledge sharing sessions between developers.
• "You Code It – You Own It" – Squad responsibility for certain functional areas of the product.

• Python, incl. additional packages/frameworks e.g., FastAPI, Pytest, PyArrow, Celery
• Go
• Databases: Redis, PostgreSQL, TimescaleDB, DuckDB
• Protocols: Kafka, MQTT, IEC104, gRPC
• Infra: Docker, Kubernetes