Staff Engineer - Core Markets

Salary: £55,000 - 95,000 per year

Requirements:

• Experience designing and building large-scale backend systems and distributed architectures.
• Strong systems design skills and experience leading cross-team technical initiatives.
• Experience with cloud infrastructure (AWS), Kubernetes, APIs, and modern backend development.
• Familiarity with AI-powered systems, Retrieval-Augmented Generation (RAG), search platforms, or vector databases.
• Strong programming experience in Python or another modern backend language.
• Comfortable influencing technical direction without direct authority.
• Excellent communication skills and a passion for mentoring engineers and raising engineering standards.
• Nice to have: experience as a founding engineer or CTO at a startup, or building systems from scratch in early-stage environments.
• Nice to have: experience modernising legacy systems.

Responsibilities:

• Define technical strategy and architecture across Platform, AI, Retrieval, and shared engineering services.
• Partner with Engineering Leaders and Staff Engineers to drive technical direction and platform investments.
• Design scalable backend systems, APIs, and shared platform capabilities.
• Guide architecture across teams, helping reduce complexity and establish common patterns.
• Partner with AI and Retrieval teams to build scalable search and RAG capabilities.
• Lead complex cross-team technical initiatives from design through production.
• Improve platform reliability, scalability, observability, and developer experience.
• Contribute hands-on to critical technical work and set a high engineering bar through design reviews, mentoring, and technical leadership.
• Leverage AI-assisted engineering to improve productivity and accelerate delivery.

Technologies:

• AI
• AWS
• Backend
• Cloud
• CTO
• Kubernetes
• Python
• RAG
• Excel

More:

We are 9fin, the AI platform powering global debt markets, with more than 300 blue-chip institutions worldwide using our product. We are a scaling startup with strong product-market fit, rapid expansion in the US, and a hybrid working model based in London. We offer competitive salary, equity options, pension, private medical insurance, paid sick leave with income protection, group life assurance, season ticket loan and cycle to work schemes, 25 holiday days plus local public holidays, the ability to work abroad for up to 3 months a year, a paid sabbatical after 5 years of service, enhanced parental leave, flexible working arrangements, and a professional learning and development budget. We also invest in quarterly team socials, summer and winter company events, and an inclusive workplace where everyone can belong.

last updated 35 week of 2026