About us

We are champions of rail, inspired to build a greener, more sustainable future of travel. Trainline enables millions of travellers to find and book the best value tickets across carriers, fares, and journey options through our highly rated mobile app, website, and B2B partner channels.

Great journeys start with Trainline 🚄

Now Europe’s number 1 downloaded rail app, with over 125 million monthly visits and £5.9 billion in annual ticket sales, we collaborate with 270+ rail and coach companies in over 40 countries. We want to create a world where travel is as simple, seamless, eco-friendly and affordable as it should be.

Today, we're a FTSE 250 company driven by our incredible team of over 1,000 Trainliners from 50+ nationalities, based across London, Paris, Barcelona, Milan, Edinburgh and Madrid. With our focus on growth in the UK and Europe, now is the perfect time to join us on this high-speed journey.

Introducing Machine Learning & AI at Trainline

Machine learning is at the heart of Trainline’s mission to help millions of customers make sustainable travel choices every day. Within our AI & ML community, we build and operate production-grade systems that power search, pricing, personalisation, marketing optimisation, and increasingly, intelligent AI agents that transform customer support and journey discovery.

As a part of Trainline, you will be joining an environment where learning and development are top priorities. You will have the opportunity to work with fellow ML enthusiasts on large-scale production systems, delivering highly impactful products that make a difference to our millions of users.

About the Role

We are looking for a Machine Learning Engineer to join the Travel team to help shape the future of rail travel. You will work on highly impactful machine learning systems that power train tracking, arrival-time predictions, and next-generation ticketing solutions, such as pay-as-you-go travel. Working alongside engineers, scientists and product managers, you will tackle complex real-world problems using geospatial data, graph representations of transport networks and advanced machine learning techniques.

As a Machine Learning Engineer at Trainline, you will...

Work in cross-functional teams combining data scientists, software, data engineers, machine learning engineers, and product managers
Design and deliver scalable machine learning systems that drive impactful, real-world applications
Work with complex and large-scale datasets to solve challenging business and customer problems
Contribute to innovative products and features that enhance the travel experience for millions of users
Own the full end-to-end machine learning delivery lifecycle, including data exploration, feature engineering, model selection and tuning, offline and online evaluation, deployment and maintenance
Partner with stakeholders to propose and develop data-driven solutions leveraging Trainline’s rich datasets and advanced algorithms
Create tools, frameworks and libraries that accelerate ML product delivery and improve team workflows
Take an active part in our AI and ML community and foster a culture of rigorous learning and experimentation

We'd love to hear from you if you...

Have a strong understanding of machine learning fundamentals and core modelling techniques, with experience applying them to real-world problems
Are proficient in Python and common ML/data libraries (e.g. Pandas, Numpy, Scikit-learn) and have experience working with large-scale data processing frameworks such as Spark
Have experience building and productionising machine learning models, including real-time systems, with knowledge of MLOps, APIs and CI/CD practices
Have strong communication skills and are comfortable presenting complex ideas to non-technical audiences
Have experience or interest in geospatial data, graph-based methods or network modelling (highly desirable)
Experience in relevant industry such as travel, mobility or transport, or related industries such as logistics, aviation or supply chain (highly desirable)

Our technology stack

Python and associated ML/DS libraries, including (Scikit-learn, Numpy, LightGBM, Pandas and, TensorFlow)
PySpark
AWS cloud infrastructure, including ECR, : EMR, ECS, S3, Athena, PostgreSQL, PostGIS, Redis and DynamoDB.
MLOps tooling , including Terraform, Docker, Airflow, MLFlow, Jenkins, GitHub Actions and Spacelift.

More information:

Enjoy fantastic perks like private healthcare & dental insurance, a generous work from abroad policy, 2-for-1 share purchase plans, an EV Scheme to further reduce carbon emissions, extra festive time off, and excellent family-friendly benefits.

We prioritise career growth with clear career paths, transparent pay bands, personal learning budgets, and regular learning days. Jump on board and supercharge your career from day one!

We're operate a hybrid model to work and ask that Trainliners work from the office a minimum of 60% of their time over a 12-week period. We also have a 28-day Work from Abroad policy.

Our values represent the things that matter most to us and what we live and breathe everyday, in everything we do:

💭 Think Big - We're building the future of rail
✔️ Own It - We focus on every customer, partner and journey
🤝 Travel Together - We're one team
♻️ Do Good - We make a positive impact

We know that having a diverse team makes us better and helps us succeed. And we mean all forms of diversity - gender, ethnicity, sexuality, disability, nationality and diversity of thought. That's why we're committed to creating inclusive places to work, where everyone belongs and differences are valued and celebrated.

Interested in finding out more about what it's like to work at Trainline? Why not check us out on LinkedIn, Instagram and Glassdoor!