About Differential.
Differential was founded on a simple observation: the gap between a data scientist and an ML engineer who can ship to production is enormous, and most hiring processes don't see it.
We exist to close that gap. We work exclusively with financial services firms looking for production ML/AI engineers and data engineers who have built the real thing — in regulated environments, at scale, under pressure.
We are not a generalist agency. We don't cover every technology or every sector. We cover one niche, and we cover it properly.
Sarah Bostock — Founder
Sarah has 20 years of recruitment experience. She started Differential after identifying a consistent market failure: companies hiring data scientists when they needed engineers, and recruiters who couldn't tell the difference.
She works exclusively across production ML/AI engineering and data engineering in financial services, across London and New York.
David Bostock — Co-Founder
David joined Differential as Co-Founder in 2026, bringing strategic and commercial leadership to the business. He oversees business development, brand, market intelligence, and the firm's expansion into New York.
Who we are.
We work in one niche. We don't place software engineers, project managers, or generalists.
We understand the technical detail — well enough to assess candidates, not just pass CVs.
We move quickly and don't waste your time.
20 years of recruitment experience, applied to a market that most recruiters don't understand.
Areas of Expertise.
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LLMs, agentic AI, RAG, MLOps, model deployment at scale
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with genuine engineering depth, in regulated financial services environments
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Azure, AWS, GCP, Databricks, Medallion architecture, modern data stacks
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Fintech, asset management, capital markets, investment banking, hedge funds, private equity-backed technology businesses, banks, and insurance firms