Head of Machine Learning Engineering

Stack

Responsibilities

• ▹Define the vision, strategy and roadmap for ML across the Core Experience pillar
• ▹Own the pillar's budget (cloud infrastructure, vendor costs, third-party tooling), balancing short-term delivery with longer-term platform investments
• ▹Lead multiple teams through their team leads, coach managers and senior ICs, and set hiring strategy
• ▹Build a culture of technical excellence, experimentation and delivery
• ▹Partner with Product, Engineering and commercial stakeholders to identify high-value opportunities and raise ML adoption across the business
• ▹Drive delivery across search relevance, payments models, splits and fare optimisation, supply automation and conversational AI
• ▹Ensure teams ship end-to-end, from prototyping through deployment, monitoring and iteration
• ▹Raise operational maturity for ML systems in production: SLIs/SLOs, incident management, on-call practices
• ▹Co-own the operating model for modern AI at Trainline (LLM-based features, agentic systems, evaluation frameworks, guardrails)
• ▹Drive improvements in AI governance, data privacy, security and audit accountability as capabilities scale

Requirements

• ▹Significant experience building and leading production ML teams, including managing through team leads (manager-of-managers)
• ▹Strong track record of shipping ML systems with measurable business or customer impact, across problem types such as ranking, recommendation, forecasting, optimisation or real-time decisioning
• ▹Deep understanding of the full ML lifecycle and strong software/platform instincts, including MLOps tooling and practices
• ▹Experience raising operational standards: SLIs/SLOs, monitoring, incident management and production reliability
• ▹Budget ownership, including infrastructure cost management and vendor oversight
• ▹Comfortable operating at both strategic and technical levels, with strong stakeholder and communication skills
• ▹Experience hiring, mentoring and developing technical talent at multiple levels

Nice to have

• ▹Experience with AWS cloud infrastructure
• ▹Experience with cross-functional delivery in product-led organisations
• ▹Experience deploying conversational and agent-based systems in customer-facing products
• ▹Experience in travel, transport, marketplaces or similarly complex digital platforms

Soft skills

What we offer

• ▹Private healthcare and dental insurance
• ▹Generous work-from-abroad policy (28 days)
• ▹2-for-1 share purchase plans
• ▹EV scheme to reduce carbon emissions
• ▹Extra festive time off
• ▹Family-friendly benefits
• ▹Transparent pay bands, personal learning budgets and regular learning days
• ▹Hybrid model: office at least 60% of the time over a 12-week period

About the company

Trainline is Europe's most downloaded rail app and works with over 270 rail and coach companies in more than 40 countries. The FTSE 250 company has over 1,000 employees based in London, Paris, Barcelona, Milan, Edinburgh and Madrid.