Staff AI Engineer

About the role

Plum is building an AI-driven proactive money platform that gives people trusted, personalised financial guidance. It is looking for a Staff AI Engineer to work across its AI Platform and Wealth Advisor teams, which together make AI-driven financial advice safe, accurate and accessible. The role shapes the technical direction of AI at Plum, connecting LLM-powered products, backend systems and financial infrastructure.

Key responsibilities

• Architect and design the core AI platform components, from model orchestration to retrieval (RAG), agentic workflows and prompt and context management.
• Lead end-to-end development of LLM-powered customer experiences for the Wealth Advisor, from system design and tool integration through deployment, monitoring and iteration in production.
• Build evaluation systems including golden datasets, LLM-as-judge grading, regression gates and offline-to-online metric correlation.
• Design guardrails, safety and observability layers (tracing, cost and latency monitoring, content and action controls) for a regulated environment.
• Drive the AI strategic vision and roadmap, evaluating emerging models, tools and techniques.
• Promote continuous improvement through architectural standards, engineering best practices and operational excellence.
• Mentor Senior Engineers and other team members.
• Work with Staff Engineers, Product Managers, Data Scientists and Compliance to deliver AI solutions that meet the standards of a regulated financial product.

Required profile

• Proven technical leadership, with experience designing, shipping and operating LLM-powered systems at scale.
• Strong software engineering fundamentals and hands-on experience across the modern AI stack.
• Rigorous evaluation methodology and the ability to make data-backed go/no-go decisions.
• Ability to communicate complex technical and architectural challenges to technical and non-technical executives.
• Experience in a cross-functional team and the ability to resolve conflicts across teams.
• Awareness of safety, fairness and regulatory considerations is a strong plus.

Required skills

• Agentic systems (tool use, orchestration, multi-step planning)
• RAG and retrieval pipelines
• Prompt engineering and fine-tuning
• Python, distributed systems, APIs and cloud infrastructure

What we offer

• Stock options and private health insurance
• Annual training budget and Plum Max subscription
• Referral scheme and flexible remote working (at least 2 days a week in London, Athens or Cyprus)
• 25 days holiday plus bank holidays and 45 work-from-anywhere days
• Sabbaticals after 4 and 8 years, enhanced parental leave, wedding allowance and annual team trip