The Foundations squad owns the platform that makes Lean's AI ambitions real the shared libraries, developer infrastructure, and agentic loops that engineers across the company depend on every day. As Staff Engineer, you'll be the technical heartbeat of the team: the person who makes the hard architectural calls, keeps standards high under delivery pressure, and ensures that what we build today doesn't become tomorrow's bottleneck.

• Drive architectural decisions for the Foundations squad setting direction on system design that balances robustness, reliability, and pragmatism, and defending those decisions with clarity

• Serve as the technical voice of the team externally building trusted relationships with other Staff Engineers and EMs across the org, and contributing to Lean's technical advisory group

• Own and evolve the team's shared libraries and platform components (including Commons) that the wider engineering organisation depends on

• Stay deeply embedded in team operations spotting friction, championing improvements to processes and service hygiene, and driving change without formal authority

• Lead by example on operational excellence: observability, alerting, SLOs, and incident response as first-class engineering concerns

• Bring informed, opinionated perspective on AI and agentic systems staying current with the industry, pushing the team's thinking, and maintaining high standards as the space evolves fast

• Mentor and coach more junior engineers, investing in those around you as much as in the code

NB. While we think the above experience could be important, we re keen to hear from people that believe they have valuable experience to bring to the role. If you identify with the team and mission, but not all of our requirements, then please still apply!!

Desired Candidate Profile

Must-have

• Staff Engineer level or equivalent you've operated at this level and know what it means to lead technically without hierarchy

• Habitual AI-assisted developer you use AI tooling as a natural, daily part of how you write, review, and reason about code

• Deep backend engineering experience: distributed systems, APIs, and reliability at scale

• Java and Spring Boot our core stack; non-negotiable

• Strong system design and architectural judgement: opinionated, defensible, and intellectually honest when better evidence arrives

• Active service ownership mindset observability, alerting, SLOs, and incident response are part of your job, not someone else's

• Comfortable leading without authority: you influence through credibility, not title

• Strong communicator you can hold a technical conversation with an engineer and a strategic one with a VP

• Invested in the people around you mentoring and growing junior engineers is something you do because you care, not because it's on your job description

Nice to have

• Experience with AI/ML integration or agentic systems (LLM orchestration, agent frameworks, production prompt engineering)

• Experience building internal developer platforms or shared libraries

• Background in fintech, open banking, payments infrastructure, or financial data APIs

• Arabic language skills