Junior Machine Learning Engineer
Trainline
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Benefits offered by this job
Job summary
Trainline is hiring a Junior Machine Learning Engineer to shape the future of AI-driven rail travel. You will join a cross-functional team of engineers, scientists and product managers to tackle complex challenges using Trainline’s data and cutting-edge algorithms.
You’ll work on end-to-end ML delivery in production environments, learning from seasoned ML professionals while delivering high-impact ML products for millions of users.
Qualifications
- Advanced degree in CS/Math or similar quantitative discipline.
- Proficiency in Python and data libraries (Pandas, NumPy, Scikit-learn).
- Experience productionising ML models.
- Expertise in predictive modeling, classification, regression, optimisation or recommendations.
- Experience with Spark.
- Knowledge of DevOps: Docker, Terraform; ML Ops platforms like MLFlow.
Responsibilities
- Design and deliver ML models at scale with measurable business impact.
- Own end-to-end ML lifecycle: data exploration, feature engineering, evaluation, deployment, maintenance.
- Collaborate with data scientists, engineers and product managers in cross-functional teams.
- Build tools and libraries to accelerate ML delivery and improve workflows.
- Contribute to AI/ML community and promote rigorous experimentation.
- Handle data extraction and feature engineering across datasets.
Skills
Education
Tools
Job description
At Trainline, our purpose is to empower greener travel choices, connecting people and places. 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.
At Trainline, our purpose is to empower greener travel choices, connecting people and places. 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.
We’re Europe’s leading independent rail platform, helping millions of travellers find and book the best-value rail and coach journeys across our app, website and partner channels.
Our job is to make the green travel choice the best choice. By building a better train travel experience, we help more people choose rail - creating a positive impact for customers, our business and the planet.
We’re a team of more than 1,000 Trainliners from over 50 nationalities, working across London, Paris, Barcelona, Milan, Edinburgh and Madrid. Now is a brilliant time to join us and help shape the future of travel.
- Advanced search and recommendations capabilities across our mobile and web applications
- Pricing and routing optimisations to find the best fares for customers
- Personalised user experiences enhanced by Reinforced Learning Agents & Generative AI
- Data-driven digital marketing systems
- AI agents improving customer support
Our machine learning teams own the complete delivery lifecycle from ideation to production. We work closely with stakeholders across the business to expand the understanding and impact of machine learning and AI throughout Trainline.
We are looking for a Junior Machine Learning Engineer to join our team help shape the future of train travel. You will be part of a highly innovative AI and ML platform working alongside engineers, scientists and product managers to tackle complex challenges by combining Trainline’s rich datasets with cutting edge algorithms. What unites our team is an expertise in the field, a love of what we do and the desire to create impactful solutions to support Trainline’s goals of encouraging sustainable travel.
As a part of Trainline you will be joining an environment where learning and development is top priority. 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.
- Work in cross-functional teams combining data scientists, software, data and machine learning engineers, and product managers
- Design and deliver machine learning models at scale that drive measurable impact for our business
- Own the full end to end machine learning delivery lifecycle including data exploration, feature engineering, model selection and tuning, offline and online evaluation, deployments and maintenance
- Work with MLE Team and Stakeholders to help design and deliver data driven products using Trainline's extensive datasets and modern machine learning techniques
- Create the tools, frameworks and libraries that enables the acceleration of our ML products delivery and improve our workflows
- Take an active part in our AI and ML community and foster a culture of rigorous learning and experimentation
- Have an advanced degree in Computer Science, Mathematics or a similar quantitative discipline
- Are proficient with Python, including open-source data libraries (e.g Pandas, Numpy, Scikit learn etc.)
- Have experience productionising machine learning models
- Are an expert in one of predictive modeling, classification, regression, optimisation or recommendation systems
- Have experience with Spark
- Have knowledge of DevOps technologies such as Docker and Terraform and ML Ops practices and platforms like ML Flow
- Have experience with agile delivery methodologies and CI/CD processes and tools
- Have a broad of understanding of data extraction, data manipulation and feature engineering techniques
- Are familiar with statistical methodologies.
- Have good communication skills
- Understanding and/or hands-on experience of Reinforcement Learning theories, frameworks, and algorithms
- Experience with cloud infrastructure
- Experience with Large Language Models (fine tuning, RAG, agents)
- Experience with graph technology and/or algorithms, understanding of NLP algorithms
- Python and associated ML/DS libraries (scikit-learn, NumPy, LightGBM, Pandas, TensorFlow, etc...)
- PySpark
- AWS cloud infrastructure: EMR, ECS, Athena, etc.
- MLOp/DevOps: Terraform, Docker, Airflow, MLFlow, NewRelic
- Recruiter Call (30 minutes)
- Meeting a Machine Learning Manager (30 minutes)
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 operating a hybrid model 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.
- 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!
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