Middleware Engineer

About mobile.de

mobile.de is Germany’s largest vehicle marketplace, with more than 1.6 million listed cars, commercial vehicles, motorcycles, and e-bikes (annual average 2025). Both private customers and registered vehicle dealers use the platform and benefit from more than 140 million visits per month*. As a “one-stop shop,” mobile.de’s offering includes not only buying and selling, but also financing and leasing solutions. Founded in 1996, the company is a subsidiary of Adevinta, a global leader in online classified portals.

Based in Berlin-Charlottenburg, we offer a dynamic environment where growth, learning, and collaboration are at the heart of everything we do. If you are driven by an eagerness to disrupt, have a passion for collaboration, and are excited about shaping the future of mobility, we would love to hear from you.

What You’ll Do & Who You Are

As a Middleware Engineer, you’ll build and run the integration layer that connects our systems and enables reliable data and process flows across the company. In this role you provide or connect to several interfaces within the company. Starting from classic ETL batch processing to event based Kafka / SOA web service integration - with a strong focus on stability, maintainability, and pragmatic engineering.

Core stack (today): Talend (ESB runtime), Java, Apache Camel, ActiveMQ, Kafka.

Job Requirements

What you bring (must-have)

• 3+ years of hands-on experience in middleware, ETL and/or interface development and integrations
• Strong practical experience with Java development in agile, cross-functional teams.
• Excellent understanding of HTTP, REST APIs, and JSON; good familiarity with common data formats (e.g., XML/CSV).
• Solid foundation in Linux, databases, and networking fundamentals (cloud exposure such as AWS is a plus, not required).
• A structured problem-solving approach with a focus on root-cause analysis and sustainable fixes.
• Ability to work independently, learn quickly, and communicate clearly with technical and non-technical stakeholders.
• Fluent English.

Nice to have

• Experience with Apache Camel patterns and integration/service testing approaches.
• Practical experience with CI/CD pipelines (e.g. Github actions).
• Knowledge of integration security, secrets management and data privacy best practices.
• Experience integrating with CRM/ERP systems (e.g., Salesforce, Microsoft Dynamics 365 Business Central).
• German language skills.

Job Responsibilities

What You’ll Do

• Design, build, and operate application integration solutions (ETL + API/messaging) with a focus on reliability, performance, and maintainability in a cloud based runtime environment
• Work with stakeholders, developers, and architects to clarify requirements and translate them into integration designs, mappings, transformations, and error-handling concepts.
• Implement and maintain java-based integration services using visual Talend IDE.
• Build and support messaging/event-driven integrations using ActiveMQ and Kafka (e.g., retries, routing, dead-letter handling, correlation/traceability concepts where applicable).
• Own day-to-day operations during business hours: troubleshooting, incident resolution, patching, and continuous improvements (no on-call duty).
• Plan and execute upgrades, migrations, consolidations, and configuration changes with minimal disruption.
• Maintain strong documentation: architecture notes, runbooks, and change records that enable others to operate and support the platform.
• Continuously improve how we do integrations (standards, templates, automation, observability and quality practices).

Job Benefits

Working at mobile.de comes with its perks! Enjoy the following benefits (some of many):

• Rewards: competitive base salary and participation in the company’s incentive programs.
• Plan for the Future: On top of the statutory retirement insurance, we offer a competitive company pension scheme.
• Team-Building: Regular team and company events offer the opportunity to network and learn from each other.
• Learning & Development: Keep growing with access to coaching, learning platforms and resources.
• Mobility: Stay mobile with a monthly transportation allowance.
• Enjoy working: Our well‑equipped office supports focused work and teamwork - plus inviting social zones where colleagues can relax and connect
• Flexible working: a hybrid approach with the option to work abroad for a set number of days per year.
• Wellbeing: confidential employee assistance and support services available to employees and their immediate families.
• Family support: enhanced parental leave and family‑friendly policies to support all parents and careers.

Meaningful Work

We are a diverse, international, highly skilled and passionate team committed to a world where people share more and waste less. Every day you will have the opportunity to make a huge difference for our users, customers as well as shape the future.

Embracing AI

We're at the forefront of integrating cutting-edge AI technologies into our operations. Being part of mobile.de you will work with and learn about AI tools, contributing to projects that leverage AI to enhance efficiency, improve customer experiences, and drive our mission forward. With an AI-first mindset, we foster a culture of continuous learning and experimentation, empowering our team to explore and apply AI in meaningful ways for the company and themselves.

Growth and Development

We are a global organisation who truly believes in growing our people. To support this we offer lots of development and training opportunities and provide a budget for our team members.

Connection and Inclusion

Our culture is the glue that holds us together. We believe in making meaningful connections and creating an inclusive atmosphere with lots of opportunities to connect both in your day to day work and through social team activities (online and offline).

mobile.de is an equal opportunity employer and we value diversity. We do not discriminate on the basis of race, religion, colour, national origin, gender, sexual orientation, age, marital status or disability status.

(*Source: mobile.de Google Analytics Tracking, average per month January to December 2025)