Senior AI/ML Engineer

Flo; Greater London; On-site; GBP 90,000 - 130,000; Full time

Benefits offered by this job

ESOP

Parental leave

Learning budget

Flexible work arrangement

Job summary

Flo is hiring an AI/ML Platform Engineer to join the AI Platform team. You will work at the intersection of machine learning engineering and MLOps, owning development and operationalization of AI/ML systems.

Responsibilities span fine-tuning models to building scalable deployment pipelines and monitoring frameworks. You will work with LLMs, AI judges for safety, and CI/CD for ML workflows in a cross-functional setting.

Qualifications

• Experience with machine learning systems and ML infrastructure is essential.
• Strong Python programming skills and CI/CD for ML workflows advantageous.
• Experience with LLMs, fine-tuning, evaluation and model deployment is beneficial.

Responsibilities

• Develop, fine-tune, and optimise large language models for health domains.
• Build and maintain ML infrastructure, CI/CD pipelines, and model deployment tooling.
• Ensure safety, compliance and scalable evaluation frameworks across AI workloads.

Job description

• We are looking for an AI/ML Platform Engineer to join the AI Platform team
• This team builds and maintains Flo’s shared platform for artificial intelligence, enabling every product team to use AI safely, efficiently, and at scale
• In this role, you will work at the intersection of machine learning engineering and MLOps, owning both the development and operationalization of AI/ML systems
• Your responsibilities will span from fine-tuning and optimising large language models to building and maintaining the infrastructure that enables rapid experimentation and reliable deployment at scale
• You will work with state-of-the-art technologies including LLMs, model evaluation frameworks, and modern ML infrastructure to build solutions that are medically safe and work at scale
• The AI Platform team acts as the central enabler of machine learning and AI initiatives across the organisation
• Its mission is to reduce operational overhead and maximise ROI from ML use cases
• The team builds and maintains critical infrastructure including LLM evaluation frameworks (AI Judges), model deployment pipelines, fine-tuning infrastructure, user profiles store, experiment tracking systems, and monitoring frameworks
• By working closely with domain teams, the AI Platform team delivers scalable, high-quality solutions that accelerate time-to-market while ensuring compliance and maintaining the highest standards of performance
• Develop, fine-tune, and optimise large language models for domain-specific health applications, working with both proprietary and open-source models (Gemini, GPT, Llama, etc)
• Design and maintain automated pipelines for model training, fine-tuning, evaluation, and deployment across diverse AI workloads
• Build and enhance LLM evaluation frameworks (AI Judges) for measuring model safety, medical accuracy and performance
• Implement CI/CD practices for ML/AI engineering workflows, including experiment tracking, model versioning, and automated testing
• Orchestrate seamless deployment of models, AI agents and inference endpoints with automated testing and rollback capabilities
• Implement comprehensive monitoring for model performance, drift detection, AI safety metrics, and responsible AI compliance
• Constantly improve technical capabilities by researching and implementing best practices in the rapidly evolving space of LLMs and generative AI
• Work in a cross-functional setup alongside other Flo Teams (Product, Security, Analytics, Marketing, Legal, etc)

Benefits

• Participation in Flo’s success: We firmly believe every employee contributes to the company’s growth and its future success. All employees are eligible to participate in Flo’s Employee Share Ownership Plan (ESOP) and be awarded equity to participate in the long-term value creation of the business
• Family benefits: We know having a baby can be a big transition for the family, so we’re proud to offer 1 month fully paid paternity leave to be there and bond with your baby and 6 months of fully paid maternity leave, with a $5000 bonus on your return to work to help you settle into this new chapter of your life. (Depending on your country there may be additional options for parental time off and shared parental leave beyond the early days)
• Resources you need to thrive: At Flo you will have access to internal and external learning resources and tools to challenge your knowledge and push yourself further every day. We support career progression from within through personal development plans and dedicated Learning & Development budget to help you thrive
• Holiday and sick leave: It’s important to take time off to recharge and spend time with family and friends. We offer 25 days (28 for vice presidents and above) paid holiday in addition to the local public holidays and 30 days fully paid sick leave per year
• Flexible workplace: We want to provide a setup that gives our employees the flexibility they need, while also getting important face to face time with the team. With this in mind, we encourage teams to spend 2 days/week in the office.

Our popular Workation policy also allows you to work from anywhere for up to 2 months a year

7+ years of professional experience in machine learning, with hands-on experience building and deploying production-grade AI/ML systemsIf you’re passionate about cutting-edge generative AI technologies and driven by building robust ML infrastructure that delivers value to millions of users, we would love to hear from you!Excellent communication skills and ability to collaborate with diverse teamsCommitment to responsible AI practices, including fairness, accountability, and transparencyAbility to devise creative solutions to intricate technical challenges, including experience in systems design with the ability to architect and explain ML/LLM pipelinesDatabricks (or similar tooling) platform experience with Unity Catalog, MLflow, and Databricks Machine Learning for end-to-end AI/ML workflowsExperience with modern ML infrastructure tools such as MLflow, experiment tracking systems, and model registriesRecent engineering experience with LLM infrastructure and tooling, including fine-tuning (LoRA, SFT or other), prompt engineering, and model evaluationCloud platform expertise with one of the Hyperscalers (AWS, GCP, or Azure) including AI-specific servicesStrong Python programming skills for efficient model development, experimentation, and deploymentUnderstanding of the entire ML/LLM development lifecycle, including CI/CD, version control, testing, and agile methodologiesOur strength is in our differences. At Flo, hiring is based on merit, skill and what you bring to the role – nothing elseAI safety and governance experience with model evaluation, LLM judges, bias detection, and responsible AI practicesExperience building and managing data pipelines using tools like Apache SparkAI model serving experience with modern inference servers and API gateways for AI applicationsFamiliarity with statistical fundamentals and running and evaluating experimentsInfrastructure as Code experience with Terraform, Ansible, or other IaC toolsExperience with LLM fine-tuning techniques including LoRA adapters, preference optimisation (RLHF/DPO), and model distillationExperience in the MedTech or HealthTech domainExperience at a Tier-1 product company or related experience working within a product organisationContainerisation and orchestration experience with Docker, Kubernetes, and ML-specific operators