Senior Python Developer (m/f/d)

Who we are operates at the intersection of energy and technology: It is our mission to  combat climate change by providing medium to large energy consumers the tools to transition away from fossil fuels. To achieve this, we are building a B2B software solution that empowers our customers to make smarter energy decisions, increasing the speed of green transformation while also achieving significant cost savings. From the start, sustainability is central to both our product and our company, and we live this as part of our daily work.

Your opportunity

You will be one of the first engineers to join’s tech team. This will put you at the forefront of our product development. You will be working directly with our founders and have the opportunity to shape our team in its early stages. You’ll build services from the ground up, using your skills to make key architectural decisions and define our workflows. Your passion for finding new solutions to important problems and shaping a young organization will make you a fundamental contributor to

Who we’re looking for

You’re a senior-level Python extraordinaire who’s as comfortable with end-to-end application engineering as you are with writing a tidy, powerful script. If your toolkit isn’t a perfect match for our list, but you have a willingness to adapt and learn, you might just be the spark we’re looking for.

Caring as much about making an impact on the planet and customers as you do about technology and data? Then please consider applying. Whether you’re a backend engineer with a data affinity, a machine learning researcher looking to build a product, or anywhere in between – it’s your drive to discover the path towards achieving our mission that will set you up for success at Needless to say, our initial solutions have to be pragmatic rather than perfectly (over-)engineered, but we are ready to grow and scale together with you.

Your role

On your journey with, you will build scalable web services, architect new solutions, and dive headlong into developing our product from the ground up. Specifically, your role will focus on full-stack (data) application development, ranging from python-based web application / platform development, architecture and operations (DevOps/ MLOps) to data visualization, analysis and simple frontend development. In all of this, you are not afraid to start scrappy: You like to move with lightning speed to build, get feedback and learn new things.

Yet, if your toolkit isn’t a perfect match for our list, but you have a willingness to adapt and learn, you might just be the spark we’re looking for.

We celebrate work-life synergy

At, we understand that everyone’s journey is different, and we are passionate about diversity, family friendliness, and flexible work arrangements. Our founders lead by example, working diligently while juggling parental responsibilities and working from abroad. We are committed to giving everyone the flexibility they need to thrive in our inclusive and supportive culture.

Tech skills we are excited about

  • Strong web / backend development expertise using Python (Flask/Django)
  • Experience in software architecture for web services, ideally with data focus
  • Some affinity to frontend development (e.g. Javascript/React)
  • An eye for building things from scratch and making quick, informed decisions
  • Solid understanding of both relational and non-relational databases (preferably PostgreSQL and MongoDB)
  • Understanding of containerization technologies (preferably Docker and/or Kubernetes) and cloud computing platforms (ideally AWS)

Bonus if you’re familiar with

  • Data engineering, data warehousing, data architecture
  • Basic data analysis / machine learning methods (ideally for time series data)
  • Infrastructure-as-Code (IaC), e.g. Terraform

Join the Revolution

Are you ready to power up your career while igniting positive change in the world of energy? Apply now to be part of onu’s vibrant, driven team and let’s make a sustainable difference, one kilowatt-hour at a time!

Get in Touch is an equal opportunity employer. Our commitment to inclusivity is woven into the fabric of our culture:

We believe in fostering a workplace that celebrates diversity and respects each individual’s unique journey. We are committed to a hiring process that is inclusive by design, ensuring that no candidate is discriminated against on the basis of gender identity, sexual orientation, personal expression, ethnicity, religious beliefs or disability status. We encourage all applicants to omit personal information such as pictures, age, or marital status from their applications, as we focus solely on evaluating candidates based on their qualifications and merit. Our goal is to provide a positive candidate experience, and we welcome candidates to communicate any accommodations they may need during the hiring process.