AI-native cybersecurity startup stopping email-based attacks before they reach the inbox

Backend Software Engineer

San FranciscoOn-site$170K - $220K2 - 4 yearsReferral bonus eligible
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Business email compromise costs organizations billions annually, and traditional rule-based defenses keep falling short. We're building an AI detection engine that learns how organizations communicate internally and externally, flagging account takeovers and impersonation attempts inside Microsoft 365 environments—often within seconds of a credential breach. You'll design the distributed systems that ingest, normalize, and analyze massive volumes of email and identity telemetry, turning raw signals into high-fidelity threat detections. The work spans real-time event pipelines, graph-based behavioral models, and APIs that surface risk to security teams without adding friction to their workflows. This is a small, focused engineering group where your code ships directly into production and shapes how the platform reasons about deception.

What they're looking for

  • 2–4 years of backend engineering experience building production services, ideally in NodeJS or TypeScript
  • Comfort working across languages—our stack touches Python, Go, Rust, Java, or C/C++ depending on the problem
  • Experience designing and operating event-driven architectures, message queues, or streaming pipelines at scale
  • Familiarity with identity protocols (OAuth, SAML), Microsoft Graph API, or the Microsoft 365 security ecosystem is a strong plus
  • Instinct for shipping incrementally and iterating based on real-world data without sacrificing reliability

Tech stack

NodeJSTypeScriptReactPythonGoRustJavaC

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