Senior Software Engineer – Real-Time Data Platform in London

We’re looking for a Senior Software Engineer to join our team building and operating the core data platform that powers our business. This platform sits at the heart of everything we do, delivering high-quality, real-time market data to systems and teams across the organisation. If you enjoy working on high-throughput, low-latency systems at massive scale, and want to take ownership of meaningful, business-critical problems, this role is for you.

About the Role

You’ll be working on a distributed, event-driven platform responsible for processing billions of market data messages per day. This is a high-performance environment where reliability, scalability, and correctness are essential. Our platform acts as the backbone of the business, ensuring that accurate and timely market data flows seamlessly to downstream systems that depend on it for analytics. You’ll collaborate closely with engineers, product teams, and stakeholders to design, build, and operate resilient systems that handle extreme data volumes with precision—while also maintaining a strong focus on cost efficiency, scalability, and operational excellence.

Key Responsibilities

• Design and build scalable, real-time data processing systems using technologies like Apache Flink, Kafka.
• Develop high-quality, maintainable code for Apache Flink (Java) data processing and .NET APIs.
• Lead and contribute to collaborative system design, while taking end-to-end ownership of implementation through to production support.
• Build production-grade systems with a strong focus on observability, monitoring, and operational excellence, enabling rapid detection and resolution of issues.
• Work with AWS services to build cloud-native, highly available systems.
• Define and manage infrastructure using Terraform.
• Implement CI/CD pipelines and deployment workflows using tools like Harness.
• Optimise systems for performance, latency, throughput, and cost.

What We’re Looking For

• Excellent collaboration and communication skills.
• Strong experience in distributed systems and event-driven architectures.
• Hands-on experience with: Apache Flink (or similar stream processing frameworks), Kafka or other messaging systems.
• Strong proficiency in .NET or Java.
• Experience building systems that are highly observable and operationally mature, with strong monitoring, logging, and alerting practices.
• Strong understanding of performance tuning, scalability, and fault tolerance.
• Good understanding of cost implications when designing systems, including the ability to project costs as we scale.

Why Join Us

• Work on systems that are mission-critical to the entire business.
• Operate and evolve a platform handling billions of messages per day.
• Solve complex engineering challenges at massive scale.
• Be part of a team that values ownership, collaboration, and delivery.
• Opportunity to shape a high-performance, cost-efficient, and highly observable data platform.

If you’re motivated by building robust, scalable systems that operate under constant load, and want to have a direct impact on a platform the entire business depends on, we’d love to hear from you.

Base Salary Compensation Range: GBP 68,333.33. Bonus Target: 12.5% Annual. We expect the compensation and target bonus for this role to fall within the stated range. The specific compensation offered will depend on the candidate’s qualifications, experience, and other job-related factors.

The company's hybrid work environment gives you the opportunity to collaborate in-person each week as we've found that we're at our best when we're purposely together on a regular basis. In most of our locations, our hybrid work model is four days in-office each week. A range of other benefits are also available to enhance flexibility as needs change. No matter where you are, you'll have tools and resources to engage meaningfully with your global colleagues.