This position is at Adevinta España

The selection process will be entirely managed by Adevinta España.

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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. We are looking for a technical fraud analyst to join our growing fraud team. You’ll work at the intersection of data, product, engineering, and CS. Using your analytical and technical skills, you will identify fraudulent behaviour, monitor for credential stuffing attacks, bot attacks, build pro-active rule based defenses, and influence the roadmap to keep Kleinanzeigen safe marketplace. This is a hybrid role, based in Barcelona Spain. What you’ll do:

- Analyze fraud patterns using marketplace and behavioral data to uncover new attack vectors, emerging threats, and operational gaps.
- Monitor and respond to credential stuffing attacks, leveraging signals from login, IPs,



device fingerprinting, and rate limiting systems.
- Design and implement technical fraud rules, filters, and tools in collaboration with engineering to align fraud prevention efforts and resolve complex incidents.
- Contribute to the strategic fraud prevention roadmap by identifying opportunities for improvements and automation.
- Support incident response and post-mortems for major fraud events, ensuring learnings feed into product and policy improvements.
- Stay current on industry fraud trends, and tools, bringing external insights to help us stay ahead of attacks.

Who you are:
- 4+ years of experience in fraud analytics, trust & safety, or a similar technical role in a C2C marketplace or traditional e-commerce environment.
- Strong proficiency in SQL and experience with data analysis tools (Tableau, Python, etc.).
- Familiarity with bot detection,

📌 Technical Fraud Specialist (Barcelona)
🏢 Adevinta España
📍 Barcelona