Senior Software Developer - Fraud Prevention

About the role

Wise is hiring a Senior Software Developer for its Fraud Risk team in Tallinn, Estonia. The team builds fast, accurate, real-time risk decisions on transfers and customer profiles, using data, automation and AI-driven signals to prevent fraud before it happens. The role combines hands-on development with technical leadership, mentoring and cross-team collaboration.

Key responsibilities

• Build the systems that prevent fraud and scams through real-time transfer and profile decisioning
• Own the technical roadmap and deliverables of key projects in the prevention domain
• Drive improvements in latency, reliability and decision quality across the decisioning platform
• Address technical debt, keep risk within appetite and enforce engineering best practices (observability, security, Kafka/DB usage, testing)
• Mentor engineers, share knowledge, lead onboarding and interview future talent
• Contribute to guilds and cross-team engineering efforts to reduce duplicated work

Required profile

• Strong experience building and operating production systems on Java/JVM, with expert-level knowledge of your technical discipline
• Track record of owning the technical direction of large projects, from design and RFCs through delivery and long-term operation
• Experience designing systems with long-term iteration and scaling in mind, documented API-first interfaces and a proactive approach to technical debt
• Accountability for reliability, security and observability, including incident resolution and post-incident reviews
• Ability to explain the purpose and expected impact of work and give feedback on the product roadmap
• Experience mentoring engineers and collaborating across Product, Data Science, Fraud Operations and Analytics

Required skills

• Java/JVM
• Distributed systems and event-driven architectures (Kafka or similar)
• Nice to have: Python, machine learning concepts, deploying models in production or working with large language models in production

The team is based in Budapest and Tallinn, and the application goes directly to Wise's careers page.