Senior Software Engineer (f/m/d) Python Developer

At IONOS, the leading European provider of cloud infrastructure, cloud services and hosting services, you will work together with a wide range of teams. We are characterized by open structures, a friendly working culture and flat hierarchies with a strong team spirit. We firmly believe that work and fun are compatible, and offer you the right environment for this. Our constant growth means that we are always looking for new colleagues. Become part of IONOS and grow with us.

Join our agile development team as a Senior Python Developer and take a leading role in transforming our platform’s architecture, building internal tools, and contributing to a modern, scalable infrastructure.

Tasks

• Refactor our existing Django monolith into modular microservices deployed on Kubernetes (k8s).

• Implement necessary frontend changes in React-based application (SPA).

• Design and develop highly customized administration tools to support internal business operations.

• Ensure these tools run reliably and efficiently to assist DevOps and Support teams.

• Build and maintain CI/CD pipelines for rapid testing and deployment.

• Actively participate in code reviews — both giving and receiving constructive feedback.

• Collaborate with internal departments to understand needs and deliver solutions.

• Work independently to plan, implement, and document projects.

• Translate high-level user stories into clear technical requirements.

Qualifications

• Passion for writing clean, testable, and maintainable code.

• Strong experience with Python and frameworks such as Django or Flask.

• Proficiency in using ORMs and writing efficient SQL (ideally PostgreSQL).

• Solid understanding of Git workflows (including rebase and interactive rebase).

• Familiarity with modern software testing practices and a desire to maintain high test coverage.

• Good knowledge of JavaScript, React (or similar frameworks), HTML, CSS, and jQuery. Hands-on experience with CI/CD tools and practices.

• Working knowledge of Linux (preferably Debian).

• Experience with Kubernetes and Helm is a strong plus.

You are:

• A proactive problem solver with a critical mindset.

• A clear and thoughtful communicator.

• A collaborative team player who values shared ownership and learning.

We believe in empowering developers to make decisions, take ownership of their work, and grow both personally and professionally. If you’re excited about working in a fast-moving environment with real impact — we’d love to hear from you.

Location: Berlin

Language: Fluent English skills (written and spoken).

Benefits

• Hybrid working model.

• Flexible working hours through trust-based working hours.

• At some locations a subsidized canteen and various free drinks.

• Modern office space with very good transport connections.

• Various employee discounts for activities and products.

• Employee events such as summer and winter parties, as well as workshops.

• Numerous training and development opportunities.

• Various health offers, such as sports and health courses.

About IONOS

IONOS is the leading European digitalization partner for small and medium-sized businesses (SMB). The company serves around six million customers and operates across 18 markets in Europe and North America, with its services being accessible worldwide. With its Web Presence & Productivity portfolio, IONOS acts as a 'one-stop shop' for all digitalization needs: from domains and web hosting to classic website builders and do-it-yourself solutions, from e-commerce to online marketing tools. In addition, the company offers Cloud Solutions to enterprises who are looking to move to the cloud as their businesses evolve.

We value diversity and welcome all applications - regardless of, for example, gender, nationality, ethnic or social origin, religion, disability, age as well as sexual orientation and identity, physical characteristics, marital status or any other irrelevant factor subject to applicable law.