Senior Backend Engineer (d/f/m) - Fixed Term contract

Kleinanzeigen; Berlin; On-site; EUR 90,000 - 130,000; Full time

Benefits offered by this job

Hybrid working

20 days work from anywhere

Parental leave

Personal development budget

Transportation allowance

Free shipping on Kleinanzeigen Direktk

Pension and life insurance

Annual company sports events

Corporate benefits & discounts

Referral program

Job summary

Kleinanzeigen is seeking a Backend Engineer for the Transactions area (TRX) to shape the money-related parts of the platform. You’ll own services from implementation to production in a modern Java stack, working with Spring Boot, PostgreSQL, Kafka, and external partners.

This maternity leave replacement runs through January 2027. You’ll tackle complex distributed systems, ensure observability, testing, and code quality, and collaborate with teams to deliver reliable payment and shipping

Qualifications

• Solid professional experience in backend software engineering with Java and Spring Boot.
• Hands-on experience with event-driven architectures and Kafka.
• Experience with PostgreSQL, migrations, automated testing, and modern engineering practices.
• Approach problems with observability, logs, metrics, and testing to craft sustainable solutions.
• Experience using AI-supported engineering tools to improve development and quality.

Responsibilities

• Build, evolve, and maintain backend microservices using Java and Spring Boot.
• Own services in production, triaging alerts with logs and metrics.
• Design event-driven systems with Kafka and reliable messaging patterns.
• Model complex workflows around transactions, payments, shipping, and partner integrations.
• Work with PostgreSQL and Flyway for data models and migrations.
• Ensure high quality via unit/integration tests and consider AI tools to improve workflows.

Skills

Java

Spring Boot

Event-driven architecture

Kafka

PostgreSQL

Testing (unit/integration)

Observability & debugging

AI-assisted tooling

Tools

Kafka

Flyway

Testcontainers

PostgreSQL tooling

Job description

Job Description

Join the Kleinanzeigen Transactions area (TRX) as a Backend Engineer and help shape the transaction experience on Kleinanzeigen. TRX is responsible for the money-related parts of our platform, including experiences such as “Direkt kaufen”, as well as the shipping processes connected to transactions. We integrate and work closely with external partners including our Payment Service Provider and shipping partners.

You’ll work hands‑on with a modern Java stack, take ownership of services from implementation through production, and solve complex business and technical challenges that directly impact our users.

This is a temporary maternity leave replacement until January 2027.

Job requirements

Who You Are

• You have solid professional experience in backend software engineering with Java and Spring Boot and are comfortable owning production services.
• You have hands‑on experience with event‑driven architectures and Kafka and understand patterns for building reliable distributed systems.
• You are confident working with PostgreSQL, database migrations, automated testing, and modern engineering practices.
• You approach complex problems systematically, using observability, logs, metrics, and testing to understand issues and develop sustainable solutions.
• You actively explore and use AI-supported engineering tools and practices to improve development, problem‑solving, and software quality.

Job responsibilities

What You’ll Do

• Build, evolve, and maintain backend microservices using Java 25 and Spring Boot.
• Take end‑to‑end ownership of your services in production, including triaging alerts and investigating issues using structured logs and metrics.
• Design and implement event‑driven systems with Kafka, including reliable messaging patterns such as the outbox pattern.
• Model complex business workflows around transactions, payments, shipping, and integrations with external partners.
• Work with PostgreSQL and Flyway to design, evolve, and maintain reliable data models and database migrations.
• Ensure high software quality through comprehensive unit and integration testing, including Testcontainers, while using AI tools thoughtfully to improve your engineering workflow.

Job benefits

Your benefits at Kleinanzeigen

At Kleinanzeigen, we care about our people — their wellbeing, growth, and life beyond work. Our benefits are designed to support you holistically, giving you flexibility and opportunities to thrive.

Flexibility

• Flexible working time (hybrid)
• 20 days “work from anywhere”
• Paid additional parental leave for both parents
• Extra paid days off for special occasions (e.g. your wedding or a move)

Wellbeing & Support

• Confidential support & coaching for you and your loved ones
• Annual company sports events
• Pension and life insurance

Growth & Development

• Personal development budget
• Learning opportunities to grow your skills and career

Perks & Everyday benefits

• Corporate benefits and exclusive discounts
• An attractive referral program
• Transportation allowance
• Free shipping on Kleinanzeigen Direktkauf

Kleinanzeigen is an equal opportunity employer that values diversity and inclusion. We welcome people of all backgrounds, races, religions, colours, national origins, gender identities, sexual orientation, ages, marital status, or disability.

If this role sparks your interest but you’re not sure you meet every single requirement, we’d still love to hear from you anyway.