Fractional Data Science Lead (FP&A) (2-3 days per week)

G MASS; Greater London; Hybrid; GBP 221,000 - 332,000; Full time

Benefits offered by this job

Hybrid work in London

Job summary

G MASS is partnering with an international fund and corporate services organisation to appoint an experienced Data Science Lead who will provide senior advisory and technical guidance across a foundational data programme in London. The role is hybrid (2–3 days/week) with an immediate start and a daily rate up to £1500.

You will establish data governance, data quality KPIs, and education for FP&A and data engineering teams, defending modelling decisions to CTOs and raising capability across the

Qualifications

• 10+ years in a senior advisory/lead capacity within financial services
• Deep expertise in dimensional data modelling and schema design
• Expert SQL and Python for analysis and validation
• Experience with Microsoft data stack (Fabric, Synapse, Power BI) and Azure AIFoundry
• Ability to defend modelling decisions to technology leadership

Responsibilities

• Define and govern the modelling approach for the data mart with emphasis on future AI use cases
• Establish data science standards and best practices across FP&A and data engineering teams
• Review outputs and provide structured feedback
• Define data quality KPIs and instrumentation
• Assess analytical readiness and plan remediation sequencing
• Deliver education sessions and written standards for capability uplift
• Advise on data governance implications of downstream AI and tooling

Skills

SQL

Python

Dimensional modelling

Schema design

Semantic layer

Executive presence

Tools

Fabric

Synapse

Power BI

Azure AI Foundry

Job description

ace has partnered with a prestigious, leading international fund and corporate services organisation to appoint an experiencedData Science Leadwho will provide senior advisoryand technicalguidance across a foundational data programme, at the point where the structural decisions are being made.

Our client is midway through asignificant changeagenda:consolidatinga fragmented core administration estate andinvesting seriously in clean data, consistent data processes, and data quality measurement. This is aseniorrole focused on judgementandoutput. You will sit alongside an internal data lead, a small data engineering function and an FP&A team, and your mandate is to make sure they build the right thing — bringing genuine data science fundamentals totheteam,challenging structural decisions before they become expensive, and leaving the organisation more capable than you found it.

The successful candidate will be equally comfortable defending a modelling decision to a CTO and teaching a schema fundamental to an FP&A analyst.

Responsibilities

• Define and govern the modelling approach for the client's new data mart: schemaselection, grain, conformeddimensionsand semantic layer structure — with explicit focus on avoiding decisions that foreclose future analytical or AI use cases.

• Establish data science fundamentals and good practice across the FP&A and data engineering teams:

• Modelling discipline, statistical rigour,reproducibilityand documentation standards

• Review of the team's own output, with structured feedback

• Define data quality dimensions, KPIs and measurement approach, and advise on how these are instrumented and reported.

• Assess the analytical readiness of the current data estate and set the sequencing for remediation and cleansing work.

• Deliver structured education and upskilling — working sessions and written standards — so capability persists beyond the engagement.

• Advise on the data governance implications of downstream AI and agentic tooling, including client-data segregation, permissible-usecontrolsand auditability.

• Provide a clear, honest read on where the client genuinely needs sustained data science capability versus where existing capability simply needs tuning.

• Substantial financial services domain experience — fund administration, corporate or fiduciary services, asset servicing, wealth,bankingor insurance. Candidates must understand the fundamentals of the business, not only the shape of the data.

• Senior practitioner background, typically 10+ years, with meaningful time in an advisory, lead or principal capacity where the deliverable was a recommendation rather than a model.

• Deepexpertisein dimensional data modelling, schemadesignand semantic layer architecture; able to articulate and defend the trade-offs between competing modelling approaches.

• Expert SQL; strong Python for analysis and validation.

• Practical experience of the Microsoft data stack — Fabric, Synapse, Power BI semantic models, and ideally Azure AI Foundry.

• Demonstrable experience defining data quality frameworks and KPIs in an enterprise setting.

• Evidenced capability-building experience. A material part of this role is raising the standard of an existing team.

• Executive presence and credibility with technology leadership and finance stakeholders.

• Comfortable operating at enterprise, not internet, data scale.

Please note that this role is expected to 2or 3days per week,hybrid in London. Start date isideallyimmediate, with the ability to earn up to £1500 a day.