# Staff Data Scientist at marshmallow

> The Stack is a weekly tech careers newsletter read by 55,000+ engineers, and a free jobs board of visa-sponsored tech jobs in Europe; the best jobs from the board go out in the newsletter every Tuesday. This is one job from the board.

> Responsibilities: - Lead technical design and delivery of ML

- **Company:** marshmallow (https://jobs.trythestack.co/companies/marshmallow)
- **Location:** London, United Kingdom
- **Work arrangement:** Hybrid
- **Employment type:** Full-time
- **Experience level:** 10+ years
- **Visa sponsorship:** Offered, according to the listing
- **Key skills:** Machine Learning, Generative AI, LLM, Risk decisioning, Fraud detection, System-level thinking, Statistical rigour, Data science, Stakeholder management, Production deployment, Technical leadership, Automation, Product strategy, Engineering collaboration, Model integration
- **Posted by employer:** 2026-10-06
- **Added to The Stack:** 2026-10-07
- **Listed until:** 2026-12-05
- **Status:** Active
- **Apply:** https://jobs.ashbyhq.com/marshmallow/ecb457b5-1773-496c-a8b5-fabec42759e2 (the employer's own application page)
- **Human page:** https://jobs.trythestack.co/jobs/staff-data-scientist-marshmallow

## About the role

Responsibilities:
- Lead technical design and delivery of ML and Generative AI systems for Claims and Fraud, from prototypes to production.
- Shape system-level architecture: how models, data pipelines and workflows fit to scale decisioning and reduce time-to-production.
- Drive platform and tooling improvements (monitoring, feedback loops, QA) that enable reliable AI-driven claims automation.
- Collaborate with Product and Engineering to align technical choices with commercial goals and multi-year automation strategy.
- Set and enforce high standards for experimentation, statistical rigour, measurement and uncertainty communication to stakeholders.
- Mentor and influence other data scientists, advocating for robust, maintainable solutions.

Requirements:
- Significant commercial experience building and shipping production ML systems and Generative AI/LLM solutions.
- Strong statistical foundations and experience designing experiments and evaluating model performance.
- Proven system-level thinking: architecture, monitoring, feedback loops and maintainability in production environments.
- Track record of influencing cross-functional technical direction and communicating with senior stakeholders.
- Comfortable working with engineering teams to deploy, monitor and operate models; product-minded and outcome-focused.

## Responsibilities

Provide technical leadership for data science in claims and fraud, focusing on scaling decisioning and automating the claims journey. Design and deploy production-grade machine learning and generative AI systems while collaborating with cross-functional teams to ensure robust, scalable solutions.

## Requirements

Requires significant commercial experience in end-to-end machine learning and hands-on experience shipping generative AI systems in production. Candidates must possess a strong statistical foundation and proven ability to influence technical direction across data science and engineering teams.

## FAQ

- **Is this Staff Data Scientist role still open?** It was posted on 2026-10-06 and is listed as active on The Stack. Confirm on marshmallow's application page before applying.
- **Does marshmallow offer visa sponsorship?** This listing is marked as offering visa sponsorship. Eligibility rules are set by the employer, so check the details on marshmallow's site.
- **Where is this role located?** The listing gives the location as London, United Kingdom. It is marked hybrid.
- **What skills does this role ask for?** The listing names: Machine Learning, Generative AI, LLM, Risk decisioning, Fraud detection, System-level thinking, Statistical rigour, Data science, Stakeholder management, Production deployment, Technical leadership, Automation, Product strategy, Engineering collaboration, Model integration.

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## Notes for agents

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