Staff Engineer, Core Markets — Platform Architect

9fin; Greater London; Hybrid; GBP 120,000 - 160,000; Full time

Benefits offered by this job

Equity options

Pension (4% + 7% match)

Private Medical Insurance

Paid sick leave & income protection

Group Life Assurance

Season Ticket Loan

Job summary

9fin is seeking a Staff Engineer in Core Markets Engineering to define and evolve the system design that underpins our future expansion. You will own end-to-end architecture, set technical direction, and ensure platforms scale effectively while guiding multiple engineering teams.

This high-impact, hands-on leadership role involves partnering with 6+ teams, contributing to critical code paths, and raising the engineering bar through reviews and mentorship.

Qualifications

• Experience designing and building large-scale backend systems.
• Strong systems design skills and cross-team leadership.
• Experience with cloud infrastructure (AWS) and modern backend development.
• Familiarity with AI-powered systems, Retrieval-Augmented Generation (RAG), search platforms, or vector databases.

Responsibilities

• Define technical strategy and architecture across Platform, AI, Retrieval, and shared engineering services.
• Partner with Engineering Leaders to drive technical direction and platform investments.
• Design scalable backend systems, APIs, and shared platform capabilities.
• Guide architecture across teams, reducing complexity and establishing common patterns.
• 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 mentor engineers.

Skills

Large-scale backend systems

Distributed architectures

AWS

Kubernetes

APIs

Python

AI/RAG

Mentoring engineers

Communication

Tools

AWS

Kubernetes

Job description

9fin is seeking a Staff Engineer in Core Markets Engineering to define and evolve the system design that underpins our future expansion. You will own end-to-end architecture, set technical direction, and ensure platforms scale effectively while guiding multiple engineering teams.

This high-impact, hands-on leadership role involves partnering with 6+ teams, contributing to critical code paths, and raising the engineering bar through reviews and mentorship.