Full Stack Engineer

Kleinanzeigen; Madrid; Hybrid; EUR 60,000 - 120,000; Full time

Benefits offered by this job

Private health insurance

Gym Pass

Remote working allowance

Personal development budget

Flexible working hours

Annual holidays

Job summary

Kleinanzeigen, Germany’s leading online classifieds platform, is seeking a Backend-Heavy Full Stack Engineer to power high-traffic services. You’ll own end-to-end development from design to deployment, balancing robust backend with polished frontend in TypeScript and React.

You’ll work on microservices in Java/Spring Boot and Go, integrate with AWS/Kubernetes/Kafka, and contribute to CI/CD practices in a highly autonomous, hybrid team.

Qualifications

• Experience designing and scaling microservices with Java and Spring Boot.
• Hands-on experience with Go and frontend integration using TypeScript/React.
• Experience with high-throughput, low-latency systems.
• Familiar with CI/CD and Agile team practices.

Responsibilities

• Architect scalable microservices supporting 36M+ monthly users.
• Own full development lifecycle from design to deployment.
• Deliver end-to-end user experiences by integrating backend APIs with TypeScript/React frontends.
• Drive improvements in testing standards and CI/CD pipelines.

Skills

Java

Spring Boot

Golang

Python

TypeScript

React

NextJs

Kubernetes

AWS

Kafka

CI/CD

Tools

Vitest

Playwright

CloudFormation

Job description

Job Description

Kleinanzeigen reaches 36M+ monthly users and is Germany’s leading online classifieds market. We are a sustainability-focused platform where you won't just write code; you will power the services that bridge our high-traffic backend with seamless user experiences.

Job Requirements

Joining the Edge team means working on the bedrock of Kleinanzeigen, dealing with high-throughput, low-latency and highly-efficient services that require a 'you build it, you run it' mindset, offering you deep exposure to modern infrastructure and platform architecture.

What You’ll Own

As a Backend-Heavy Full Stack Engineer, you’ll be a central driver for the services that power user privacy and media delivery at scale. You will own the full development lifecycle: from design and implementation to deployment and maintenance. Your impact will include:

• Core Systems Architecture: Designing and scaling critical microservices using mostly Java and Spring Boot that support 36M+ monthly users.


• Full Lifecycle Responsibility: Applying \"build it, run it\" mentality—you aren't just writing code; you’re ensuring robustness, scalability, and observability in production.


• End-to-End Delivery: Crafting seamless user experiences by integrating our robust backend APIs with high-quality, maintainable frontends in TypeScript and React.


• Strategic Engineering: Driving improvements in our development practices, testing standards, and CI/CD pipelines to keep our team velocity high and our systems healthy. For frontend components, you will maintain high standards using tools like Vitest and Playwright.

Our Tech Toolbox

We believe in picking the right tool for the job. Our core environment is built on modern technologies, including:

• Backend: Java, Spring Boot, Golang, python


• Frontend: NextJs, React, TypeScript


• Infrastructure & Messaging: AWS, Kafka, CloudFormation, Kubernetes

We value technology-agnostic engineers who are comfortable navigating this stack and are open to learning new technologies as our systems evolve.

How We Work

• Autonomy: We operate in a highly autonomous, cross-functional environment where teams own their services end-to-end.


• Methodology: We follow Agile methodologies with a focus on code quality, pair programming, and CI/CD best practices.


• Balance: We work in a hybrid configuration that values flexibility, deep focus time, and collaborative problem-solving.

Job Responsibilities

• Architectural Mindset: You have proven experience building systems at scale (load balancing, service discovery, dynamic routing, circuit breakers). You understand not just how to build features, but how they perform under load.


• Owner’s Mentality: You seek out challenges, take the lead on troubleshooting complex production issues, and are proactive in proposing long-term technical solutions.


• Technical Mentor: You elevate the engineers around you through thoughtful code reviews, collaborative pair programming, and a commitment to sharing best practices.


• Effective Communicator: You can navigate trade-offs between speed and technical debt and explain your decisions clearly to the wider team.


• Tech Stack: You have strong experience in Java/Go, and you are comfortable balancing that deep backend work with frontend execution using React/TypeScript.

Flexibility

• 26 business days of paid annual holidays


• 20 days “work from anywhere”


• Flexible working time (hybrid)


• Paid additional parental leave for both parents


• Extra paid days off for special occasions (e.g. your wedding or a move)

Wellbeing & Support

• Private health insurance


• Gym Pass (may cover up to 70% of gym membership fees)


• 40€ per month as a remote working allowance.

Growth & Development

• Personal development budget


• Learning opportunities to grow your skills and career


• A unique position in an international and dynamic environment


• A flat, collaborative culture where your feedback actively shapes our processes

Perks & Everyday Benefits

• Competitive compensation package (Base salary + annual bonus)


• Flexible Remuneration Program (tax-efficient options for transport, restaurant vouchers and childcare)


• Corporate benefits and exclusive discounts


• An attractive referral program

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 status.

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!