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Halcyon

Principal Kernel Engineer

Job Summary

Halcyon is seeking an experienced Principal Kernel Engineer to develop and enhance their Windows security agent, focusing on preventing, detecting, and responding to ransomware attacks. The role involves developing prototypes, translating prototypes into production code, and driving feature development, bug fixes, and performance improvements. The candidate should have strong skills in C++, Windows kernel internals, and driver development, with a bonus for experience in reverse engineering and telemetry. The company offers comprehensive benefits and promotes a remote, collaborative work environment.

Required Skills

Performance Optimization
Rust Programming
C++ Programming
Reverse Engineering
Multithreaded Programming
Kernel-mode development
User-mode development
Windows API
NT kernel internals
Memory debugging
Driver development
Windows Mini-Filter drivers
Telemetry development
Tools for Rust/C++ interoperability

Benefits

Parental Leave
Flexible PTO
Disability Insurance
401k Plan
Comprehensive Healthcare
Life and AD&D Insurance
FSA Options
Equity Offering

Job Description

What we do:
Halcyon is the industry’s first dedicated, adaptive security platform that combines multiple proprietary advanced prevention engines along with AI models focused specifically on stopping ransomware.

Who we are:
Halcyon was formed in 2021 by a team of cyber industry veterans after battling the scourge of ransomware (and advanced threats) for years at some of the largest global security vendors. Comprised of leaders from Cylance (now Blackberry), Accuvant (now Optiv), Fireye and ISS X-Force (now IBM), Halcyon is focused on building products and solutions for mid-market and enterprise customers.

As a remote-native, completely distributed global team, we recognize great talent can exist anywhere. We invite you to apply to a job you’re interested in and we'll work a plan to meet your needs.

The Role:

Halcyon’s goal is to deliver an anti-ransomware solution that breaks new ground as to what an amazing security product can deliver. Aligned with this goal, Halcyon is looking for an experienced Principal Kernel Engineer to contribute to our Windows agent’s ability to prevent, detect, respond, and remediate attacks. In this role, you will drive enhancements in multiple product domains. This development will allow Halcyon’s product to better protect customers from the threat of ransomware.

Responsibilities:

  • Develops prototypes for new features, transforms prototypes into production quality code

  • Translates learnings from prototyping effort into crisp functional specifications and project plans for new product features with minimal direction

  • Independently drives new features, bug fixes, and performance enhancements

Skills and Qualifications:

  • Writes high-quality multithread-safe code in C++ in both kernel-mode and user-mode

  • Always makes sound decisions with respect to best engineering practices

  • Develops high-quality code in Rust or a strong desire and capacity to learn quickly (Rust)

  • Has shipped at least one production quality driver for Windows NT

  • Strong knowledge of Win32 APIs and NT kernel internals

  • Debugs memory corruption issues and improves end-to-end system performance

  • Strong written and verbal communication skills

  • Highly collaborative with a strong ability and desire to mentor and inspire others

  • Practical professional experience in dealing successfully with ambiguity

Bonus skills and Qualifications:

  • Knowledge and experience with Portable Executable format, Reverse Engineering

  • Experience with Windows Mini-Filter drivers and Windows Filter Platform callout drivers

  • Experience with SQL/Databricks and prior experience developing automated telemetry

  • Familiarity with tools for Rust / C++ interoperability

Benefits:

Halcyon offers the following benefits to eligible employees:

  • Comprehensive healthcare (medical, dental, and vision) with premiums paid in full for employees and dependents.

  • 401k plan with a generous employer contribution.

  • Short and long-term disability coverage, basic life and AD&D insurance plans.

  • Medical and dependent care FSA options.

  • Flexible PTO policy.

  • Parental leave.

  • Generous equity offering.

The Company reserves the right to modify or change these benefits programs at any time, with or without notice.​

Base Salary Range: $235,000 - $275,000

Bonus Target: 10%

In accordance with applicable state and federal laws, the range provided is Halcyon’s reasonable estimate of the base compensation for this role. The actual amount may differ based on non-discriminatory factors such as experience, knowledge, skills, abilities, and location. Base pay is one part of the total package that is provided to compensate and recognize employees for their work, and this role may be eligible for additional discretionary bonuses/incentives, and equity in the Company.

We understand it takes a diverse team of highly intelligent, passionate, curious, and creative people to develop the exceptional product we are building. Our dynamic team has incredible perspectives to share, just as we know you do, and we take great pride in being an equal opportunity employer.

Interested in this job?

Application deadline: Open until filled

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Halcyon

Halcyon is the cyber resilience platform that Global 2000 companies rely upon to defeat ransomware-as-a-service-borne attacks. With the fastest endpoint recovery methods ever built and multiple layers of resiliency, including bypass and evasion protection, key capture and automated decryption, and data extortion prevention, the Halcyon platform enables attacks to be undone in minutes.

See more jobs
Date PostedMay 5th, 2025
Job TypeFull Time
LocationRemote
Salary$235,000 - $275,000
Exciting fully remote opportunity for a Principal Kernel Engineer at Halcyon. Offering $235,000 - $275,000 (full time). Explore more remote jobs on FlexHired!

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