Senior Full Stack Developer

Job description

The team you will join

Fraud Risk Team Join the Fraud Risk team, where we are dedicated to preventing fraud before it happens and keeping Wise customers safe in real time. Our mission is to stop fraudulent activity at the point of attempt by running instant checks on transfers and customer profiles, making accurate risk decisions with minimal friction. We build scalable, low-latency systems, improve our detection and decisioning tooling, and partner closely with fraud specialists to continuously raise the bar on prevention using data, automation, and AI-driven signals to reduce losses and protect legitimate customers.

Our vision

Create an automated, real-time fraud prevention experience that blocks bad activity while keeping genuine customers moving. Build fast, reliable risk decisioning capabilities for transfers and profiles, optimised for accuracy, latency, and scale. Foster a strong partnership between fraud prevention specialists and the product/engineering team to translate expert knowledge into effective controls. Use AI-driven detection and decisioning, and work closely with Data Scientists to productionise models and signals, improving precision, reducing false positives, and lowering operational costs.

What will you be working on?

Real-World Impact

Shape and build the systems that prevent fraud and scams through real-time transfer and profile decisioning.

Technical Ownership

Own the technical roadmap and deliverables of key projects in our prevention domain, delivering them predictably and with clear customer impact.

Domain & Platform Evolution

Build deep expertise across our technical and fraud domains, driving continuous improvements in latency, reliability, and decision quality across our decisioning platform.

System Health

Address technical debt, keep risk within appetite, and enforce Wise's engineering best practices (observability, security, Kafka/DB usage, testing).

Engineering Leadership

Multiply team impact by mentoring engineers, sharing knowledge to eliminate single points of failure, leading onboarding, and interviewing future talent.

Cross-Team Collaboration

Contribute beyond the team through guilds and cross-team engineering efforts to reduce duplicated work across fraud and risk domains.

Overview of the Current Team

The Fraud Risk team is a passionate group of prevention-focused crime fighters based in Budapest and Tallinn. We're a mix of engineers and fraud specialists committed to making Wise a safer platform through fast, accurate decisions on transfers and customer profiles. Our collaborative environment encourages innovation, ownership, and teamwork, making it an exciting place to work on cutting-edge solutions in fraud prevention.

Qualifications

Qualifications

Engineering Expertise: Strong experience building and operating production systems on Java/JVM, with expert-level knowledge of your technical discipline.

Distributed Systems

Solid understanding of distributed systems and event-driven architectures (Kafka or similar), including designing for low latency, high availability, and scale.

Technical Leadership

A track record of contributing significantly to large, impactful projects and owning their technical direction—from design and RFCs through delivery and long-term operation.

Long-Term System Design

Experience designing systems with long-term iteration and scaling in mind, well-documented API-first interfaces, and a proactive approach to technical debt.

Operational Excellence

Accountability for the reliability, security, and observability of the systems you build, including taking a leading role in incident resolution and post-incident reviews.

Product Mindset

Ability to articulate why something is being built, what customer problem it solves, and what impact to expect, providing valuable feedback on the product roadmap to balance protection with low friction.

Mentorship & Quality

Experience mentoring and coaching other engineers, helping raise the engineering bar through code reviews, design discussions, and best practices.

Collaboration

Excellent communication skills to collaborate effectively across functions (Product, Data Science, Fraud Operations, Analytics).

Nice to Have

Experience with Python, machine learning concepts, deploying models in production, or working with large language models in production.