Senior Full Stack Developer

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 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. For everyone, everywhere. We're people building money without borders — without judgement or prejudice, too. We believe teams are strongest when they are diverse, equitable and inclusive. We're proud to have a truly international team, and we celebrate our differences. Inclusive teams help us live our values and make sure every Wiser feels respected, empowered to contribute towards our mission and able to progress in their careers. If you want to find out more about what it's like to work at Wise visit . Keep up to date with life at Wise by following us on LinkedIn and Instagram . Wise is a global technology company, building the best way to move and manage the world’s money. Min fees. Max ease. Full speed. Whether people and businesses are sending money to another country, spending abroad, or making and receiving international payments, Wise is on a mission to make their lives easier and save them money. As part of our team, you will be helping us create an entirely new network for the world's money. For everyone, everywhere. More about our mission and what we offer .