Senior Machine Learning Engineer (M/F/D) in London

Sector: AI & DataReference: BBBH175964_1793114713Senior Machine Learning Engineer / DV Clearable / 5 Days OnsiteApplying rigorous machine learning to real‐world problems that matterWe're looking for a Senior Machine Learning Engineer to join a multidisciplinary data and AI team delivering high‐impact, real‐world solutions in a secure and highly regulated environment. This is a senior, hands‐on practitioner role, not a people‐management position. You'll operate with a high degree of autonomy, leading complex machine learning work end‐to‐end through technical depth, sound judgement, and delivery credibility. The organisation is outcome‐led rather than technology‐led. Machine learning is built in‐house only where problems are genuinely complex, niche, or sensitive - requiring experimentation, evaluation, and iteration beyond what can be bought. What you'll be doingYou'll take ownership of complex ML problems, applying scientific thinking and pragmatism in equal measure. Lead end‐to‐end machine learning delivery, from problem definition through experimentation, evaluation, and iterationApply mathematical, statistical, and scientific reasoning to form hypotheses, quantify uncertainty, and interpret resultsDesign and run structured experiments to assess model behaviour, performance, and user impactWork with real, imperfect operational data, not just curated or static datasetsCollect, assess, and transform data to support model evaluation and continuous improvementBalance rigour with pragmatism, delivering solutions that are robust, proportionate, and fit for purposeIntegrate machine learning components into wider systems, considering performance, reliability, and operational constraintsCommunicate complex technical ideas clearly to non‐technical stakeholders, enabling informed decision‐makingEngage confidently in deep technical design and review discussions with peersOperate effectively within a strong technical assurance and review cultureCollaborate with internal teams and selected external partners working at the leading edge of AIWhat we're looking forThis role suits a senior ML practitioner who values judgement, evidence, and outcomes over theoretical or tooling purity. Proven experience operating at senior practitioner level as a Machine Learning Engineer, AI Engineer, Applied ML Scientist, or equivalentStrong grounding in applied mathematics, statistics, and scientific practiceDemonstrated ability to evaluate ML models using quantitative evidence and structured experimentationExcellent Python skills for building, evaluating, and iterating on ML solutionsExperience working with real‐world, imperfect data from operational systemsStrong software engineering practices, including readable, maintainable, and well‐tested codeExperience integrating ML components into broader production systemsClear understanding of data ethics, privacy, and responsible use of dataStrong communication skills across technical and non‐technical audiencesProven ability to lead work independently and take ownership of outcomesTechnologies you'll encounterThe environment evolves, but typical tools include: Python for experimentation, modelling, and evaluationWeights & Biases (or equivalent) for experiment trackingAWS, including services such as SageMaker and BedrockInternally supported AI development platforms and toolingThis role is not suited to candidates who are dogmatic about specific tools. Desirable experienceWorking in secure, safety‐critical, or heavily regulated environmentsBackground in sectors such as energy, oil & gas, defence, or public sectorExperience within formal technical assurance or governance processesCollaboration with external suppliers, partners, or research organisationsComfort operating at pace where quality, safety, and compliance are non‐negotiableIf you enjoy solving complex problems, applying scientific thinking to messy reality, and delivering ML that stands up to scrutiny, this role offers both challenge and meaning.