Staff Backend Engineer Trust & Safety (m/w/d)

WHY THIS ROLE

Trust is what makes a real estate marketplace work: home seekers, owners and professionals all need to know that listings, accounts and interactions are genuine. AVIV's Trust & Safety organization builds the detection, scoring and verification mechanisms that protect that trust across our brands. We are building a real-time Trust-as-a-Service platform and modernizing the legacy systems behind it, and we need a technical authority to set the direction. This is an opportunity to build and improve, not simply maintain.

THE TEAM YOU'LL JOIN

You'll join Trust & Safety, working with Backend and Data Engineers, ML specialists, Product Managers and Engineering Managers, and partnering closely with Legal, Compliance and our operational moderation teams. Our next chapter is about a scalable, real-time Trust-as-a-Service platform and ML-ready infrastructure — and this role will be central to making that happen.

WHAT YOU'LL OWN

• Architecture and technical direction: Be the primary technical authority for Trust & Safety, owning the architectural roadmap across fraud detection, content quality and the trust platform.
• Trust-as-a-Service platform: Design and build a scalable, real-time platform for fraud detection, content quality, identity verification and risk scoring that other AVIV product teams can consume.
• ML systems and pipelines: Build the data collection pipelines, training and evaluation workflows, and deployment infrastructure that make our models scalable, reliable and cloud-ready.
• Real-time scoring: Design event-driven, high-throughput streaming and stateful scoring systems that process signals in real time without degrading the user experience.
• Legacy modernization: Lead the modernization and deprecation of legacy Trust & Safety systems, with safe migration paths and no loss of reliability.
• Technical leadership: Mentor Senior Engineers, raise engineering standards and influence technical decisions across multiple teams.

WHAT WE'LL ACHIEVE TOGETHER

Success in this role means creating measurable improvements, not simply introducing new processes. We expect you to help us:

• Reduce fraud through real-time risk scoring.
• Move Trust & Safety workloads onto the new platform and retire legacy systems.
• Shorten the path from model training to production deployment.
• Keep fraud checks within a latency budget with no incidents caused by them.
• Give Product and Operations reliable visibility into core risk-scoring and platform metrics. The exact measures will be agreed based on the priorities and baseline when you join.

WHAT YOU BRING

We care more about what you have built and improved than a particular title or number of years of experience. You bring:

• Strong machine learning knowledge — you understand how models are trained, evaluated and deployed, and can build the pipelines and infrastructure that run them in production.
• Significant backend engineering experience (typically 7+ years), ideally in Python, with deep expertise in distributed, high-scale systems.
• Strong hands-on AWS experience (Lambda, Kinesis, Glue, Athena, ECS) and Infrastructure as Code with Terraform.
• Experience with event-driven and real-time streaming architectures, including stateful systems and real-time scoring.
• Staff-level architecture skills: you have led large-scale legacy modernization, influenced multiple teams without direct authority and mentored senior engineers. Nice to have: experience in fraud, Trust & Safety or risk; security and GDPR knowledge; ID verification or external risk providers; marketplace experience.

HOW WE WORK AT AVIV

Our Leadership Behaviours describe not only what we expect people to deliver, but how we expect them to deliver it. For this role, four behaviours will be particularly important: Simplify to Scale. You replace legacy complexity with platform capabilities that work across teams and markets, rather than one-off fixes. Data Leads. Judgment Wins. You combine data, model evaluation and sound judgment to decide what to build and which risk signals to trust. Decide Fast. Deliver Hard. You make clear architectural decisions with the best information available and build systems that remove blockers rather than create them. Only the Best Teams Win. You raise the bar for the engineers around you through mentoring, high standards and honest technical feedback. Working model: Hybrid – 2-3 days per week in the office. Benefits:

• 30 days of holiday per year
• Hybrid work, with remote working abroad possible within the EU/EEA and Switzerland (four weeks' notice and your manager's approval)
• Company pension scheme
• JobRad
• Mobility allowance of up to €63 per month
• Urban Sports Club membership
• Mental health support with Kyan Health
• Learning and development through Juno Journey
• 2 volunteering days per year
• Corporate benefits through Axel Springer Corporate Benefits or Benefits.me
• Healthy snack and lunch selection (lunch offers depend on location)
• Office dogs welcome (pre-registration necessary) Benefits may vary by location.

WHAT TO EXPECT FROM THE HIRING PROCESS

We want our hiring process to be focused, transparent and respectful of your time. You can typically expect five steps: a 30-minute initial screening, a 60-minute technical screening, a 60-minute coding interview, a 60-minute system design interview and a 60-minute interview with the hiring manager. Your application is then reviewed by our Hiring Committee. We aim to wrap up within 2–3 weeks. We'll explain the process from the start and keep you informed throughout.

ABOUT AVIV GROUP

Join one of the world's largest and most innovative digital real estate tech companies. Backed by global investment leaders KKR and CPP Investments, AVIV Group is reshaping the way people across Europe buy, sell, rent, lease, and value real estate. With a strong presence in Europe, we power some of the region's most recognized digital real estate platforms across various countries – including Immoweb, SeLoger, and Meilleurs Agents (France's leading real estate valuation platform), alongside immowelt and Homeday (one of Germany's fastest-growing PropTech companies). Our European footprint is complemented by our dynamic tech and engineering hubs in Romania and Croatia. Our mission? We simplify life's most important transactions. By combining data, technology, and human expertise, we empower millions of people to find their perfect home! Help us shape the future of real estate.