Our client, a Leading HFT trading firm, is seeking a Senior Software Developer (Development Tools) to join one of their top-performing desks in London. In this role, you will, Senior Software developer, will design, build, and optimize tools and platforms that enhance developer productivity and strengthen engineering workflows across the organization. As Senior Software Developer you will collaborate closely with product development, infrastructure, platform engineering, security, and QA teams to deliver high‑impact, cross-functional initiatives that drive performance and reliability at scale. Responsibilities Developing enhanced tooling to boost developer productivity Maintaining and optimising CI/CD pipelines Contributing to the design and architecture of large‑scale build systems Implementing integrated monitoring, logging, and alerting for developer tooling Maintaining observability solutions across developer platforms and systems Requirements 7 years' experience with two or all skills in C++, Java or python Deep practical experience with large build systems like Monorepo-scale, Buck2 or Bazel/Blaze Strong understanding of Linux/Unix Experience with CI/CD pipelines or Git-based version systems Bachelor's degree in computer science, Software Engineering, Information Technology, or a related field or equivalent experience