Sameer Chaturvedi
Work

Security ML at petabyte scale

Microsoft

Role
Software Engineer II
Team
M365 Security Detections
When
2021 -- 2025

Four years on the petabyte-scale platform that detects cyber-attacks across all of M365 in near real time. Lead engineer for Microsoft's first mail anomaly detection and for the GPT-based detection assistant.

What I did

  • Petabyte-scale big-data platform using ML to detect cyber-attacks in near real time across all of M365.
  • Lead engineer for Microsoft's first mail-anomaly detection (response to the nation-state incident where hackers accessed executive and federal emails).
  • Lead engineer on a GPT-based security-detection assistant that analyses machine and identity activity for attack patterns.
  • Designed the production workspace that enables data-science and LLM-backed detections in an agile PySpark environment with CI/CD and realtime job monitoring.
  • Expedited detection programming by over 75% on distributed systems; auto-failover geo-replicated BCDR architecture.

Full write-up in progress. The bullets above are the short version.

Under the hood

Stack.

Security + anomaly ML

  • Mail-anomaly detection for M365
  • GPT-based security-detection assistant
  • Random-forest entity detections
  • Petabyte-scale event processing

Distributed systems

  • Spark, PySpark, Azure Functions
  • CI/CD, real-time job monitoring
  • Auto-failover geo-replicated BCDR