Principal Data Scientist | Series B | FinTech | SaaS | Scale-Up
Location: London Area, United Kingdom (Hybrid - 2 days a week on site in office)
Salary: Up to £130,000 + Equity
Skills: Machine Learning | AI | Product ML | Deep Learning | Data Platforms
Our client is a rapidly scaling Series B FinTech SaaS business backed by leading VCs. Their platform is used by top financial institutions, digital banks, and emerging fintech innovators to power real-time risk intelligence, automate decisions, and deliver data-driven financial products at scale.
As they enter their next growth phase, they're expanding their Data Science function with a Principal Data Scientist who will set the technical direction, drive product-embedded AI, and help shape the future of data intelligence in financial services.
If you're excited by high ownership, greenfield innovation, and the chance to build category-defining AI in a fast-moving scale-up — this is that role.
ROLE: Principal Data Scientist
You'll be the most senior individual contributor within Data Science — leading technical strategy, architecture, and delivery of advanced ML systems across the platform. You'll work closely with Engineering, Product, and GTM teams to build scalable, production-grade AI that directly impacts customers and revenue.
This is a hands-on leadership role where you'll combine deep technical expertise with product thinking, experimentation, stakeholder influence, and team mentorship.
What You'll Be Responsible For
Technical Leadership & Strategy
Define and own the Data Science roadmap across the Series B product suite.
Architect scalable ML systems and end-to-end pipelines that integrate directly into the core SaaS platform.
Evaluate emerging models, large language models (LLMs), and deep learning techniques to drive innovation in the FinTech domain.
Hands-On Modelling & Delivery
Build, train, validate, and deploy ML solutions across risk modelling, anomaly detection, personalisation, optimisation, and predictive analytics.
Lead experimentation cycles, champion best practices, and ensure models are production-ready.
Partner with Machine Learning Engineers to scale models, optimise performance, and improve reliability.
Cross-Functional Product Impact
Work with Product to define AI-driven features that enhance customer experience and create commercial value.
Translate complex modelling outputs into actionable insights for internal and external stakeholders.
Influence key strategic decisions in a hyper-growth environment.
Mentorship & Leadership
Coach and mentor Senior and Mid-Level Data Scientists.
Advocate for data science best practices across the organisation.
Represent the team in technical discussions, customer workshops, and industry events.
What You'll Bring
Deep expertise in ML, statistical modelling, and modern AI techniques (supervised/unsupervised, time-series, Bayesian, deep learning).
Strong Python engineering skills — NumPy, Pandas, Scikit-Learn, plus PyTorch/TensorFlow.
Experience building scalable ML systems in production (ML Ops, CI/CD for ML, model optimisation).
Proven experience in a high-growth environment (startup/scale-up preferred).
Exceptional communication and stakeholder management skills — able to influence at all levels.
Strong understanding of financial services, risk, compliance, or decision-science is a bonus.
Passion for innovation, experimentation, and solving complex problems with data.
Why Join?
High ownership role at the forefront of a scaling FinTech SaaS product.
Direct impact on roadmap, technology choices, and the future of AI within the organisation.
Equity in a fast-growing Series B business with strong backing and market momentum.
Collaborative, engineering-led culture with room to innovate.
Apply now to become the driving force behind next-generation AI in FinTech.