Senior Endpoint Engineer, EDR (linux)

SENIOR ENDPOINT ENGINEER, EDR (LINUX)

ABOUT ENT

Ent is the intent-aware workspace security platform for securing human and AI-driven work. Built to protect productivity, the new attack surface, Ent understands not just what users and agents do but why, and intervenes at the moment of risk before incidents occur. Where existing tools see events, Ent sees intent, so security teams can step in at the moment of risk instead of investigating days later. Founded by Lou Manousos and Brandon Dixon, co-founders of RiskIQ (acquired by Microsoft) and the team behind Microsoft Security Copilot, Ent is in production with Global 2000 customers across hospitality, financial services, and defense, and backed by Decibel, Sequoia, Crosspoint Capital, Craft Ventures, Shield Capital, Felicis, and In-Q-Tel. We’re now hiring the team that will define this category.

HOW WE WORK

Customer first. The product and the business are built around problems we’ve watched real security teams struggle with — not the other way around. Every roadmap conversation starts with what a CISO told us last week.

Humble. No drama. We hire people who share the mission and trust each other to deliver. Teamwork over showmanship. Accountability over politics. The work speaks louder than the person doing it.

Urgency. The window to build a durable security company in the AI era is open right now and it will not stay open. The shot clock has started. We move at the speed of the people we want to protect.

ABOUT THE ROLE

We are seeking an Endpoint Engineer to be part of the team that owns the Linux sensor at the core of Ent's EDR capability. This role builds detection and prevention on eBPF, LSM, and the audit subsystem, across the range of Linux customers actually run — workstations, servers, containers, and cloud workloads. You will own the tradeoffs between detection efficacy, false positives, and performance, and defend them with measured data.

WHAT YOU’LL ACHIEVE

• Design, build, and ship kernel- and user-mode components of the Ent agent that observe process, file, registry, network, and identity activity for Linux and turn that activity into high-fidelity intent signals.

• Own EDR-class detection and prevention capability end to end: sensor instrumentation, event enrichment, on-box correlation, and interception logic that stops malicious activity before it completes.

• Make and defend explicit tradeoffs between detection efficacy, false-positive rate, and endpoint performance, backed by measured data rather than intuition.

• Instrument telemetry at the OS boundary: eBPF, LSM, and audit subsystems.

• Harden the agent against tamper, bypass, and evasion — self-protection, integrity validation, and safe handling of untrusted input inside a privileged process.

• Hold sensor CPU, memory, and I/O inside strict budgets while processing thousands of events per second; profile hot paths and eliminate regressions before they ship.

• Build test harnesses, automated regression coverage so every efficacy claim is continuously verified, not asserted.

• Drive high-severity customer escalations to root cause — crashes, hangs, performance regressions, missed detections — at the code and OS-internals level, and convert escalation patterns into permanent fixes.

• Partner with the security research, AI, platform, and product teams to feed sensor signals into intent-aware policy enforcement, just-in-time interventions, and investigation timelines.

• Review code, mentor engineers, document design decisions, and share ownership of agent release quality and on-call.

WHAT YOU’LL BRING

MUST-HAVES

• 10+ years designing, building, and delivering production C/C++ (or Rust) systems software, a substantial portion of it in endpoint security, OS internals, or comparable performance-critical native code.

• Deep working knowledge of operating system internals: process and thread lifecycle, memory management, file systems, drivers or kernel extensions, and IPC.

• Hands-on