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Greater London, England, United Kingdom
Hybrid
Motorway is the UK's largest online car-selling platform. We connect private sellers directly with over 8,000 dealers nationwide. Our online platform helps sellers achieve great prices for their cars while giving dealers fast, reliable access to the stock they want for their dealerships. Founded in 2017, our award-winning, technology-led approach has redefined the experience of selling a car. Motorway is backed by some of the world’s leading technology investors, having raised £143 million in Series C funding.
This is a unique opportunity to join a fast-growing scale-up at a crucial phase of growth and help change an industry for the better.
GenAI Engineering sits within Motorway's Data and AI function, alongside Machine Learning and the Machine Learning Data Platform. The team owns the GenAI features that shape how buyers and sellers experience the marketplace, spanning agentic workflows in the customer experience and LLM-powered tooling for our dealer network.
Over the next two years the function scales from shipping AI features into running a serious GenAI platform. This hire is the technical authority who'll help shape that platform, working closely with engineering leadership across Data and AI and the wider Engineering org.
This is the most senior individual contributor role on Motorway's GenAI engineering ladder (IC5 / Principal). You'll report to the Director of Data and AI, advising the CPO and the wider exec on AI technical strategy. The remit is the trajectory of GenAI engineering at Motorway over a two-to-three-year horizon: the architecture, the standards and the strategic bets that no single team can absorb on its own.
You'll set architectural direction across the GenAI surface area, hold sign-off on materially complex AI systems, and have the credibility to veto implementations that don't meet our agreed technical, safety or quality bar. You'll shape the high-stakes calls on vendor strategy, model selection, build-vs-buy on platform infrastructure, and our responsible-AI posture, providing the technical rationale that lets the Director of Data and AI and the wider exec land those calls with confidence. This is still a hands-on engineering role: you'll design and build the hardest single pieces of work directly, write production code on the systems that matter most, and pair with senior engineers on the architectural decisions that will outlast specific features. You won't own all AI usage at Motorway, you won't own overall AI strategy, and you won't hold budget for AI infrastructure, but you'll contribute meaningfully to all three, and you'll define how GenAI is built and evaluated here.
This is a newly-created role and a greenfield opportunity. The technical bets you make will sit behind Motorway's most strategic AI initiatives, including ones not yet started. AI engineering choices at this level shape unit economics for years.
Set the overarching architecture for GenAI at Motorway, including reusable patterns for prompt design, RAG (hybrid retrieval, chunking, semantic caching), agent orchestration, evaluation frameworks (LLM-as-judge, golden datasets, adversarial prompts), guardrails and observability that other teams build on
Design and build the hardest single pieces of work directly, taking on the problems nobody else is well-placed to solve and leading our highest-risk, highest-reward technical bets across the GenAI surface area
Hold sign-off on architectural decisions for materially complex GenAI systems, with the credibility to veto implementations that don't meet our agreed technical, safety or quality bar
Advise the Director of Data and AI on build-vs-buy calls for AI infrastructure (vector stores, eval platforms, AI gateways, model routers, agent frameworks), and own the technical rationale behind them
Drive cost, latency and throughput optimisation across our production GenAI systems, with the trade-offs documented and explicit
Define our principles for emerging paradigms, including multi-agent protocols, multimodal systems and agent-to-agent communication
Define our responsible AI principles and keep us aligned with the EU AI Act, NIST AI RMF and ICO guidance ahead of regulatory deadlines
Own opinionated relationships with our model and infrastructure providers, with the credibility to influence vendor roadmaps where it matters to us
Coach engineers across the function, shape how we hire and review, and set the cultural bar for safety, evaluation and production quality
Identify what Motorway should stop pursuing with the same clarity as what we should start, and represent Motorway externally through publications, conference talks and meaningful open-source contributions, used as a multiplier for hiring and partnerships
Typically 8+ years building production AI/ML systems, with at least 2 years at the cutting edge of GenAI, and a track record of company-scale technical bets that have materially shifted a business's trajectory
Strong engineering fundamentals and comfort working directly in code: Python and modern API-driven architectures on cloud infrastructure (AWS or equivalent), with the production engineering instincts (CI/CD, observability, SLOs, cost attribution) to take prototypes through to hardened production
Current, hands-on expertise across the GenAI stack: LLM APIs, prompt engineering, RAG (hybrid retrieval, chunking strategy, semantic caching, re-ranking), agentic architectures (multi-step, multi-agent, tool use, memory), evaluation frameworks, LLMOps and fine-tuning
Deep understanding of LLM capabilities and limitations, including how models fail in your domain, what hallucination and prompt injection look like in practice, and how to design evals that catch them
Experience setting architectural standards adopted across multiple engineering teams over multiple years
High-stakes build-vs-buy judgment, with a clear story of where you've been right and where you've been wrong
Strategic grasp of responsible AI and AI governance, with practical experience aligning engineering decisions to NIST AI RMF, the EU AI Act or comparable frameworks
Calm, direct communication with executive and board-level audiences, with the ability to compress technical complexity into the decisions leadership needs to make
Coaching credibility with senior engineers, who have grown materially under your influence
Self-awareness as a leadership trait; you know the limits of your knowledge and pull in outside expertise before that becomes a problem
You have an external technical presence (publications, well-known open-source contributions or conference talks) and use it as a multiplier for hiring and partnerships
You've led an organisation through a major AI paradigm shift in a previous role
You have working knowledge of the ML Engineering and platform layer (serving infrastructure, AI gateways, cost attribution, multi-model routing) that GenAI features run on top of
You've advised commercial leadership on vendor and partnership strategy, including contract and data-rights negotiation
You've worked in a regulated, safety-critical or trust-heavy domain where AI behaviour has material business or legal consequence
Great work-life balance
Office location with regular social events, office drinks and free snacks to keep you going
Flexibility to work from home up to 1 day per week to help nail that work-life balance
Stock options so you can share in Motorway's growth and future success
Pension scheme to plan for your future with our provider NEST
Strong commitment to your personal development including budget for books, courses, conferences, etc
Opt-in comprehensive health insurance through BUPA and fitness discounts
Cycle to work scheme - save big ££ on a new bike and accessories
One paid volunteering day a year for you to use as you wish
Generous parental benefits including 6 months full paid maternity leave, 4 weeks paternity leave and workplace nursery scheme... and much more!
We've got your back, in life's biggest moments and the everyday ones too.
Competitive salary
Equity scheme - we all share in Motorway's success
25 days holiday
Flexible working (2 days a week in our London office, with socials and snacks galore)
Private medical insurance via BUPA
Life assurance
Pension scheme (we contribute 5%)
Enhanced family leave (e.g. 26 weeks full pay for maternity or adoption)
24/7 Employee Assistance Programme
EV leasing scheme
Cycle to work scheme
Nursery salary sacrifice scheme
1 paid volunteering day a year