Senior AI Engineer in London

We're ASOS, the online retailer for fashion lovers all around the world. We exist to give our customers the confidence to be whoever they want to be, and that goes for our people too. At ASOS, you're free to be your true self without judgement, and channel your creativity into a platform used by millions.

As a Senior AI Engineer, you'll focus on building and scaling AI-driven solutions that power personalised experiences for millions of ASOS customers. You'll design and implement robust AI systems leveraging LLMs, generative AI, and advanced data pipelines, ensuring ethical, secure, and high-performing solutions.

You'll collaborate closely with Applied Scientists, ML Engineers, and Product teams to accelerate delivery and improve the quality of AI systems by providing reusable templates, prompt engineering strategies, and infrastructure that supports experimentation.

What you'll be doing:

• Designing and developing AI solutions using LLMs and generative AI, optimising prompts and workflows for high-quality outputs.
• Building scalable data pipelines and applying advanced data preparation techniques to ensure integrity and quality.
• Driving standardisation and reusability of AI workflows, enabling consistency across diverse product domains.
• Implementing MLOps principles for AI systems — including CI/CD, model registries, monitoring, and feature management.
• Partnering with Cloud Infrastructure teams to design secure, cost-efficient environments for AI workloads.
• Embedding data ethics principles into AI development, proactively mitigating bias and ensuring safe, responsible AI practices.
• Fine-tuning pre-trained models for domain-specific tasks to improve performance and relevance.
• Designing and implementing robust evaluation frameworks for AI models, including automated testing and benchmarking.

About You:

• Professional experience as an AI Engineer or similar role, with strong exposure to LLMs and generative AI.
• Solid understanding of the end-to-end AI lifecycle, from experimentation through deployment and monitoring.
• Proficiency in Python and familiarity with ML/AI libraries (e.g., PyTorch, TensorFlow, Hugging Face).
• Experience with prompt engineering and optimisation for generative AI systems.
• Comfortable working with cloud platforms (preferably Azure) and containerisation (Docker/Kubernetes).
• Knowledge of MLOps tools and practices such as MLflow, CI/CD pipelines, and model monitoring.
• Passionate about ethical AI, bias mitigation, and improving developer experience through automation and tooling.
• Experience in fine-tuning large language models and adapting them for specific use cases.
• Strong understanding of evaluation methodologies for AI systems, including quantitative and qualitative metrics.
• Ability to design automated evaluation pipelines for continuous monitoring and improvement of AI models.

Additional Information:

• Employee discount (hello ASOS discount!)
• ASOS Develops (personal development opportunities across the business)
• Employee sample sales
• Access to a huge range of LinkedIn learning materials
• 25 days paid annual leave + an extra celebration day for a special moment
• Discretionary bonus scheme
• Private medical care scheme
• Flexible benefits allowance - which you can choose to take as extra cash, or use towards other benefits