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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Junior Machine Learning Engineer - **Company:** The Trainline - **Location:** London, UK - **Experience:** Starter - **Contract:** Permanent contract - **Skills:** Artificial Intelligence, Data Analysis, DevOps, Python (Programming Language), Machine Learning, NumPy, Recommender Systems, Data Processing, Feature Engineering, Apache Spark, Model Validation, Pandas, Scikit Learn, Information Technology, Machine Learning Operations, Terraform, Docker - **Published:** September 23, 2026 - **Apply:** https://www.indeed.com/viewjob?jk=8d0ecb2211ba00cb ## About the Role * A good working knowledge of Python, including open-source data libraries such as Pandas, NumPy or Scikit-learn * A background in Computer Science, Mathematics, Statistics or a similar quantitative discipline, whether through study or practical experience * Some exposure to building or supporting machine learning models or AI solutions, gained through study, projects or early career experience * An interest in areas such as predictive modelling, classification, regression, optimisation, NLP or recommendation systems * A curious, collaborative approach and strong communication skills, with an eagerness to learn from others * It would be helpful if you have had some exposure to Spark or similar data processing tools * You may also have some familiarity with DevOps or MLOps tools such as Docker, Terraform or MLflow * Ideally, you will have an interest in agile ways of working and CI/CD practices, though this is not essential ## Description Machine learning and AI are at the core of how Trainline is transforming travel, helping millions of customers make smarter, more sustainable journeys every day. Our ML models and AI solutions power critical aspects of our platform, including advanced search and recommendations across our mobile and web applications, pricing and routing optimisation, personalised experiences enhanced by agentic AI, data-driven marketing systems, and AI agents that improve customer support. Our machine learning teams own the complete delivery lifecycle from ideation to production, working 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 a high-performing, deeply technical community of Machine Learning Engineers, Data Scientists and Data Engineers who tackle complex problems by combining Trainline's rich datasets with cutting-edge algorithms. You will be supported to grow your skills through hands-on project work, close collaboration with more experienced colleagues, and a genuine culture of learning and development, while contributing to large-scale production systems that make a real difference to millions of customers. In this role as the Junior Machine Learning Engineer, you will... * Work within cross-functional teams alongside data scientists, software engineers, data engineers and product managers * Support the design and delivery of machine learning models and AI solutions that contribute to measurable impact for Trainline * Get involved across the machine learning delivery lifecycle, including data exploration, feature engineering, model selection and evaluation * Collaborate with stakeholders to help shape data products that make good use of Trainline's extensive datasets * Contribute to the tools, frameworks and libraries that help accelerate our ML and AI delivery and improve our workflows * Take part in our AI and ML community, sharing learning and building your experimentation skills alongside others ## Related Videos - [DevOps for Machine Learning](https://www.wearedevelopers.com/videos/179-devops-for-machine-learning) - [Shifting Stress to Progress— Understanding DevOps to do DevOps Better](https://www.wearedevelopers.com/videos/268-shifting-stress-to-progress-understanding-devops-to-do-devops-better) - [Docker Compose: Rediscovered](https://www.wearedevelopers.com/videos/1978-docker-compose-rediscovered) - [Vectorize all the things! Using linear algebra and NumPy to make your Python code lightning fast.](https://www.wearedevelopers.com/videos/562-vectorize-all-the-things-using-linear-algebra-and-numpy-to-make-your-python-code-lightning-fast) - [Machine learning 101: Where to begin?](https://www.wearedevelopers.com/videos/1014-machine-learning-101-where-to-begin) - [From DevOps to Scaled DevOps: How We’re Rebuilding Continuous Delivery as a Platform](https://www.wearedevelopers.com/videos/100018-from-devops-to-scaled-devops-how-we-re-rebuilding-continuous-delivery-as-a-platform) ## Related Articles - [How to Become an AI Engineer](https://www.wearedevelopers.com/magazine/331-how-to-become-an-ai-engineer) - [MLops – Deploying, Maintaining And Evolving Machine Learning Models in Production](https://www.wearedevelopers.com/magazine/115-mlops-deploying-maintaining-and-evolving-machine-learning-models-in-production) - [What Are Large Language Models?](https://www.wearedevelopers.com/magazine/304-what-are-large-language-models) - [The Most Popular IT Jobs on the Market](https://www.wearedevelopers.com/magazine/376-the-most-popular-it-jobs-on-the-market) - [MLOps – What’s the deal behind it?](https://www.wearedevelopers.com/magazine/125-mlops-what-s-the-deal-behind-it) - [MLOps And AI Driven Development](https://www.wearedevelopers.com/magazine/82-mlops-and-ai-driven-development)