Senior Java Software Engineer

Senior Software Engineer (Contract) – Market Data

A leading global investment management firm is seeking Senior Software Engineers (Contract) to join its Market Data Platform team on a high-impact engagement. This is a critical hire, with the opportunity to step into a highly visible area of the business where performance, scale and reliability truly matter.

This team sits at the heart of a systematic trading environment, responsible for ingesting and processing vast volumes of real-time market data through direct exchange connectivity. The platform operates at extreme scale - handling 15–20 billion data points per day, with peak rates of over 1 million events per second - and accuracy is non-negotiable.

This opportunity would suit an engineer with deep Java expertise who has worked on complete data platforms, particularly those handling real-time or market data using Kafka.

The successful candidate will be responsible for designing, developing and optimising components of a large-scale data platform used across the investment business. Working in a highly technical environment, they will:

• Build and evolve end-to-end data platforms supporting real-time and historical data use cases
• Develop primarily in Java, with Python used across parts of the wider platform
• Work extensively with Kafka and streaming architectures to handle real-time data flows
• Contribute to systems processing billions of events per day, with peak throughput in the millions per second
• Improve and modernise existing components, with a strong focus on latency, scalability and resilience
• Partner closely with data management teams, quantitative researchers and other engineering groups
• Take ownership of production systems, from requirements gathering through to deployment and optimisation

• Extensive commercial Java development experience, particularly on backend or data-intensive systems
• Demonstrable experience building or contributing to complete data platforms
• Hands-on experience working with real-time data, ideally using Kafka
• Background in market data, trading systems or other time-sensitive data domains is highly desirable
• Strong Python skills used in production environments
• Solid experience working on Linux and strong understanding of Git
• Experience with databases or data storage technologies such as Mongo
  
  DB, Postgres, Iceberg or similar
• Comfortable working in fast-paced, performance-critical environments
• Strong problem-solving skills, attention to detail and ability to work autonomously

• Experience with distributed systems and large-scale data processing
• Performance tuning and optimisation of low-latency systems
• Exposure to orchestration frameworks and modern data infrastructure
• Contributions to open-source projects
• Experience working with or around Large Language Models (LLMs)
• Rate: £500-575 per day (Inside IR35 – some flexibility for the right candidate)
• Location: Hybrid – 3 days per week onsite in the City of London.
• Start: ASAP

• 30-minute introductory discussion with the hiring manager
• 1-hour technical / programming interview with a team member
• Possible final 30-minute follow-up
• we expect at least 1 interview conducted in person