Staff Engineer - Digital Lending in London

At OakNorth, we’re on a mission to empower the UK’s most ambitious businesses. Since 2015, we’ve lent over $18 billion across the UK and US, helped create more than 58,000 new homes and 36,000 new jobs, and supported hundreds of thousands of personal savers — all while fuelling the UK economy.

Team Mission

We power OakNorth's relationship‑led lending with modern, modular tools across origination, underwriting, execution, and portfolio monitoring.

The Role

As a Staff Engineer you’ll work with product and engineering across multiple squads to ensure the right trade-offs are being made and that dependencies and communication is managed effectively. Staff Engineers are the most visible engineers in the organisation and demonstrate technical excellence and our cultural values across all squads and to teams across the wider organisation.

• Have a strong technical background, including 8+ years of experience designing and engineering large scale systems.
• Lead squads to sensible architectural decisions on the most complex technical problems.
• Measure your success in terms of business impact, not lines of code.
• Internalise the best ideas from across the organisation, humbly setting a vision that others can get behind.
• Embrace DevOps culture: You build it, you run it.
• Work well cross-functionally and earn trust from co-workers at all levels.
• Prefer simple solutions and designs over complex ones.
• Enjoy working with a diverse group of people with different areas of expertise.
• You challenge the existing approach when you see the cliff edge racing towards us, but also get on board once the options have been debated and the team has made a decision.
• You are comfortably organized amongst chaos.
• You are a broad thinker and have the capability to see the potential impact of decisions across the wider business.
• Utilise GenerativeAI: Leverage GenAI tools to increase productivity and enhance decision making processes within the role.

Nice to Have Skills

• Experience with AI/LLM integrations and Generative AI applications.
• Knowledge of intelligent document processing and NLP techniques.
• Familiarity with vector databases (e.g., Pinecone, Weaviate) and search platforms (e.g., OpenSearch, Elasticsearch).
• Exposure to agentic workflows or orchestration frameworks for multi-step AI reasoning, familiarity with MCP (Model Context Protocol), and frameworks like Claude Code.

Tech stack

We’re pragmatic about our technology choices. These are some of the things we use at the moment:

• Python
• PostgreSQL, BigQuery, MySQL
• TypeScript, React, styled-components
• Jest, React Testing Library, Cypress, pytest
• AWS, GCP
• ECS Fargate, Docker, Terraform, GitHub Actions

How we expect you to work

• Collaborate - We work in cross-functional, mission driven, autonomous squads that gel over time. We pair program to work better through shared experience and knowledge.
• Focus on outcomes over outputs - Solving a problem for users that translates to business results is our goal. Measurements focused on that goal help us to understand if we are succeeding.
• Practice continuous improvement - We optimise for feedback now, rather than presume what might be needed in the future and introduce complexity before it will be used. This means we learn faster. We share learnings in blame-free formats, so that we do not repeat things that have failed, but still have confidence to innovate.
• Seek to understand our users - We constantly seek understanding from data and conversations to better serve our users' needs, taking an active part in research to hear from them directly and regularly.
• Embrace and enable continuous deployment - Seamless delivery of changes into an environment - without manual intervention - is essential for us to ensure that we are highly productive; consider resiliency; and practice security by design.
• Test outside-in, test first - TDD keeps us confident in moving fast, and deploying regularly. We want to solve user problems, and so we test with that mindset - writing scenarios first, then considering our solution; coupling tests to behaviour, rather than implementation.
• You build it, you run it - We embrace DevOps culture and end-to-end ownership of products and features. Every engineer, regardless of their role, has the opportunity to lead delivery of features from start to finish.
• Be cloud native - We leverage automation and hosted services to deliver resilient, secure services quickly and consistently. Where SaaS tools help us achieve more productivity and better quality results for a cheap price, we use these to automate low value tasks.

How we expect you to behave

We embrace difference and know that when we can be ourselves at work, we are happier, more motivated, and creative. We want to be able to bring our whole selves to work, have our own perspectives and know that we belong. As such, through your behaviours at work, we expect you to reflect and actively sustain a healthy engineering environment that looks like this:

• A wide range of voices heard to the benefit of all.
• Teams that are clearly happy, engaged, and laugh together.
• Perceivable safety to have an opinion or ask a question.
• No egos - people listen to and learn from others at all levels, with strong opinions held loosely.

What makes working here better

This is a truly hybrid role, offering engineers the flexibility to work from home while also providing opportunities to collaborate in person with the team when it adds value. There’s no fixed requirement for days in the office, instead, we focus on creating space for engineers to engage meaningfully, whether that’s in-person for whiteboarding sessions or remote for deep focus work.

Work-life balance - 25 days holiday (plus...