Senior Software Engineer
Focussing on our Sportsbook product, we're looking for a Senior Software Engineer to help build and evolve our next-generation trading risk platform, powering real-time liability and exposure management across multiple brands and markets. You'll primarily work on our Core Liability engine - a modular, event-driven system - delivering fast, accurate, and real-time insight into live positions and risk. This platform underpins critical trading decisions and represents a major step forward in scalability, resilience, and streaming architecture across our technology estate.
- Design and build distributed, real-time streaming components within a Flink-based architecture.
- Develop and maintain services that process the full bet lifecycle, from acceptance through settlement, cancellation, and cashout.
- Implement complex financial calculations, including multi-bet and bet-builder logic, ensuring accuracy and consistency at scale.
- Build systems that aggregate exposure and generate real-time risk insights across outcomes, markets, and customers.
- Contribute to a granular alerting framework that detects and publishes meaningful changes in liability.
- Ensure correctness in a high-throughput environment through robust handling of ordering, duplication, and idempotency.
- Optimise streaming jobs for latency, throughput, and resource efficiency.
- Collaborate closely with trading and product teams to translate domain requirements into scalable, reliable systems.
- Contribute to a modular architecture where components evolve independently and scale with increasing demand.
- 5+ years software engineering experience in building distributed systems.
- Excellent Java skills
- Experience with streaming technologies (Apache Flink preferred; Kafka Streams, Spark Streaming, etc.).
- Solid understanding of event-driven architecture and asynchronous processing patterns.
- Experience handling data consistency challenges such as at-least-once processing, idempotency, and event ordering.
- Experience building high-throughput, low-latency systems in production environments.
- Ability to model complex domain logic and translate business requirements into robust technical solutions.
- Experience in cloud computing, ideally AWS.
- Proactive and ability to deal with and account for uncertainty, with the flexibility to learn by iteration.
- Nice to Have: Experience in sports betting, trading platforms, or financial systems.
- Nice to Have: Experience building real-time alerting or monitoring systems.
- Nice to Have: Exposure to modern data platforms or lakehouse architectures.
- Well-being allowance
- Learning and development opportunities
- Inclusion networks
- Charity days
- Long service awards
- Social events and activites
- Private medical insurance
- Life assurance and income protection
- Employee Assistance Programme
- Pension
FDJ United is one of Europe's largest gaming and betting groups, formed after French lottery operator La Française des Jeux (FDJ) acquired Kindred Group - the company behind Unibet - in 2024 and rebranded the enlarged group in 2025. Headquartered in Boulogne-Billancourt, France, it operates lottery, online sports betting, casino and poker across multiple European markets and Australia. Its portfolio includes well-known online brands such as Unibet, 32Red and Maria Casino, alongside FDJ's French lottery and retail network. The group is listed on the Euronext Paris exchange.
