Windows System Software Engineer

Cylake, Inc•Sunnyvale, CA

2d•$150,000 - $250,000

About The Position

Join a small team building the next generation of cybersecurity products from the ground up. Led by industry veterans with a proven track record of success - you will get to architect, build, and deliver hugely impactful products with this world class team. You will have the opportunity to grow your career and skills along with the company from the very start. We are looking for an exceptional Windows systems engineer with deep expertise in Windows kernel internals, operating system architecture, and endpoint technologies, who understands Windows below the Win32 API, from the NT kernel and executive subsystems to process lifetime management, memory internals, and modern platform security. This is not an application development, framework engineering or WinAPI-only developer role. You'll be designing and building the low-level endpoint infrastructure that powers real-time telemetry, behavioral detection, and system instrumentation across modern Windows environments. You'll work across kernel-mode and user-mode, developing production-grade systems that operate reliably in highly concurrent, security-sensitive environments.

Requirements

Extensive experience building low-level Windows systems software.
Deep expertise in Windows kernel architecture and NT internals.
Extensive experience developing Windows kernel drivers.
Strong knowledge of process, thread, memory, and object management.
Expert-level C/C++ programming skills.
Experience debugging complex multithreaded systems.
Strong understanding of synchronization, paging, interrupts, and x64 architecture.
Experience using WinDbg and kernel debugging tools.
Ability to reason about undocumented operating system behavior through analysis and debugging.

Nice To Haves

Rust experience.
Filesystem minifilters.
Windows Filtering Platform (WFP) or NDIS.
ETW provider development.
Hypervisor technologies (VT-x / AMD-V).
Secure Kernel, VBS, or HVCI knowledge.
Memory forensics or reverse engineering experience.
Symbol parsing and Windows build analysis.

Responsibilities

Design and develop production-quality Windows kernel drivers using WDM/WDF.
Build kernel instrumentation and telemetry pipelines for endpoint visibility.
Develop high-performance process, thread, and image lifecycle tracking.
Implement scalable kernel callback infrastructure using: Process notifications, Thread notifications, Image load notifications, Object callbacks, Registry callbacks.
Design lock-efficient kernel data structures and synchronization strategies.
Build reliable user/kernel communication mechanisms.
Debug complex concurrency, synchronization, and memory issues.
Work directly with Windows NT internals beyond documented APIs.
Build systems that understand process, thread, memory, and object lifecycles.
Analyze scheduler behavior, process creation, and teardown.
Work with Windows internals including: Memory management, Object Manager, Executive subsystems, ETW, ALPC, Handle tables, Tokens, Registry internals.
Investigate compatibility across multiple Windows releases.
Debug boot-time, runtime, and kernel crash scenarios.
Design telemetry systems that power endpoint detection and response.
Build behavioral detection capabilities using operating system telemetry.
Research modern attack techniques and operating system abuse.
Improve visibility into process execution, code loading, and system activity.
Design resilient monitoring systems that operate in complex enterprise environments.
Evaluate modern Windows security features and how they impact endpoint architecture.
Analyze Windows internals and system behavior.
Debug kernel crashes, memory corruption, and race conditions.
Reverse engineer operating system components when documentation is unavailable.
Use debugging and reverse engineering tools to understand low-level execution paths.