(Senior) Backend Engineer - Core Team (all genders)

About the role

Too easy is boring! Together, we are on a mission to drive forward the energy transition. We love what we do, and we are unafraid to dive in. We believe in taking ownership of our work and in continuously growing and evolving. In short: own it, love it, grow with it. We are a humble team of coffee and maté lovers with over 20 nationalities. With our geek humor, our love for emojis and random facts is only natural. Over 150 envelians are already on board. Dive in and thrive! As (Senior)  Backend  Engineer  - Core Team (all genders)  you will be part of an engineering squad with strong knowledge in software architecture, data modelling and graph-functionality.  Together, you drive the development of the GridHub - our Core Component which feeds all applications - and directly influence the experience of our users, our organization, and our engineering practices. As part of the Core team, you directly influence the shape and functionality of our Digital Twin, by designing interfaces and generalized functionality for complex requirements.
You develop and extend cross-application workflows that ensure data integrity for planning and live applications. In doing so, you always strive to capture the app-specific requirements in a universally applicable solution.
You familiarize yourself with our individual and domain-specific solutions within the modelling and calculation of electrical grids and improve them in an independent and innovative way.
You are actively involved in the design and improvement of our system architecture in the area of code, data model and infrastructure.
You exchange ideas with other developers to enable a smooth interaction between the different components.
You have +3 years of relevant experience in web application development with a focus on backend components, data modelling and infrastructure.
You have experience with relational databases in the architecture of Data Models, preferably Digital Twins, and the design of queries, preferably in PostgreSQL.
You have extensive experience with Python, ideally related to orchestration and parallelization of tasks in the context of multi-processing, e.g. with Celery.
You have experience with graph-data, e.g. through experience with graph databases or other graph tooling such as networkX.
You are a team player and passionate about working with talented and inspiring people.
You prefer complex, technical challenges and have high standards for your elaborate and intelligent solutions.
You are familiar with parts of our tech stack and are looking forward to keeping up with current industry best practices.
Optionally, you are familiar with one or more of these topics: distributed computing, graph theory and geoinformatics.
You are business-fluent in English (Level C1).
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 and Celery.
PostgreSQL.
RabbitMQ, Redis.
Docker, Kubernetes.
Flexible working mode  within Germany: Hybrid, from home or in our lovely office in Cologne 
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 your workplace)  
Support for your health through  sports membership   cooperations  
P rofessional   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