Cloudflare
Principal Data Scientist, Detection
$215K–$225K
Hybrid +2 · Principal · Full-time · Posted Sep 9, 2026
- Location
- Hybrid
London, United Kingdom
New York, New York, United States - Experience
- At least 8-10 years of professional experience in Data Science, ML Engineering, or Software Engineering.
- Visa sponsorship
- Offers may be conditioned on authorization to receive technology controlled under U.S. export laws without sponsorship for an export license.
About the job
Leads research and strategy for Internet-scale detection models that identify automated, fraudulent, and malicious activity.
What you'll do
- Design and evaluate detection models and own measurement frameworks for noisy or uncertain ground truth.
- Mentor colleagues and drive adoption of AI/ML techniques while representing Cloudflare in the research community.
- Set detection strategy and partner with ML Engineering, Data Engineering, and Product teams.
What they ask for
- Strong applied statistics, machine learning, and AI methodology fundamentals, with fluency in large-scale data.
- Professional experience in Data Science, ML Engineering, or Software Engineering.
- Ability to make ambiguous, high-stakes technical decisions with incomplete information.
- Comfort with Python and SQL in production environments.
Nice to have
- Experience in fraud, abuse, or bot detection on large, high-velocity traffic.
- Experience making progress with weak, delayed, absent, or contested labels.
Pay
$215,000 - $225,000 USD annual base salary (New York City based hires)
Tools
Python, SQL
AI focus
Researches detection models for automated, fraudulent, and malicious activity; drives adoption of AI/ML techniques.
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