Staff Backend Engineer

Staff Backend Engineer - Python, FastAPI | Architecture, Distributed Systems & AI | AI FinTech, Series C | London Hybrid or Remote | Up to £165k + Equity | Work Abroad 90 Days/Year The Company We're working with a highly successful, fast-scaling AI b2b FinTech transforming how data and workflows operate across global financial markets. Following significant growth and Series C funding, they're now heavily investing in new products and international expansion. The Role | Staff Backend Engineer - Python, FastAPI | Architecture, Distributed Systems & AI | AI FinTech, Series C | London Hybrid or Remote | Up to £165k + Equity | Work Abroad 90 Days/Year This is a high-impact Staff Engineer position on the IC track, taking ownership of technical strategy and architecture across a complex, rapidly scaling engineering organisation. Rather than owning a single product or feature set, you'll operate across multiple engineering teams, helping define the architecture and technical direction that underpins the company's next phase of growth. You'll remain hands-on when it matters, but your impact will extend far beyond your own code - setting engineering standards, solving complex architectural problems and aligning teams around a clear technical vision. You'll be working across areas including: Designing and evolving large-scale backend and distributed systemsDefining technical strategy across Platform, AI, Retrieval and shared engineering servicesDesigning scalable APIs and shared platform capabilitiesLeading complex, cross-team technical initiatives from design through to productionImproving reliability, scalability, observability and developer experienceWorking closely with AI and Retrieval teams across search, RAG and data-intensive systemsReducing architectural complexity and establishing common engineering patternsContributing hands-on to critical technical work while raising standards through design reviews and mentoringUsing AI-assisted engineering to improve productivity and accelerate delivery What We're Looking For | Staff Backend Engineer - Python, FastAPI | Architecture, Distributed Systems & AI | AI FinTech, Series C | London Hybrid or Remote | Up to £165k + Equity | Work Abroad 90 Days/Year Strong experience designing and building large-scale backend systems and distributed architecturesExcellent systems design skills, with evidence of making significant architectural decisionsExperience leading technically complex initiatives across multiple engineering teamsStrong backend programming experience with Python or another modern backend languageStrong experience with AWS, Kubernetes, APIs and modern cloud infrastructureComfortable influencing engineering strategy without direct authorityAble to move between high-level technical strategy and hands-on engineeringStrong communication skills with experience mentoring engineers and raising engineering standardsComfortable making pragmatic technical trade-offs in complex, scaling environments Experience with AI-powered systems, RAG, search platforms, retrieval systems or vector databases would be particularly valuable. Experience as a Founding Engineer / CTO, building systems from scratch in an early-stage environment, or modernising complex legacy systems would also be highly relevant. What's On Offer | Staff Backend Engineer - Python, FastAPI | Architecture, Distributed Systems & AI | AI FinTech, Series C | London Hybrid or Remote | Up to £165k + Equity | Work Abroad 90 Days/Year Up to £165,000 base salary + equityPension contribution matched up to 7%Private medical insuranceFlexible hybrid or remote workingWork abroad for up to 3 months per year25 days' holiday + public holidaysProfessional learning & development budget1-month paid sabbatical after 5 yearsSignificant influence over the architecture and technical direction of a rapidly scaling engineering organisation Staff Backend Engineer - Python, FastAPI | Architecture, Distributed Systems & AI | AI FinTech, Series C | London Hybrid or Remote | Up to £165k + Equity | Work Abroad 90 Days/Year This is an opportunity for a genuine Staff-level Backend / Platform Engineer who enjoys solving difficult systems problems, influencing architecture across multiple teams and remaining close enough to the code to lead by example.