Windows Kernel developer

Who we are

Nucleon Security is a fast-growing Deeptech startup building next-generation cybersecurity solutions powered by artificial intelligence, designed to stop the most advanced threats.

With operations across Europe and Africa, we proudly deliver 100% sovereign technology trusted by organizations of all sizes – from agile startups to global enterprises.

Our expertise? Protecting endpoints across all environments. Automating the detection of complex attacks. Empowering security teams with intuitive, high-performance platforms.

Our ambition is clear: become a global leader in cyber resilience, enabling organizations to anticipate, detect, and contain threats autonomously and securely.

Your mission

As a Windows Kernel & Agent Developer at Nucleon Security, you will design, develop, and maintain the kernel-mode drivers and user-mode components that form the core of our cybersecurity agent.

You will :

• Develop and maintain Windows kernel drivers (minifilter, WFP, callbacks, etc.).
• Build user-mode C services that communicate with the drivers to process events, apply policies, and manage the agent.
• Implement monitoring and protection features across file, network, process, and registry layers.
• Integrate advanced anti-tampering mechanisms, with the possibility of adding an ELAM driver later.
• Ensure stability, compatibility, and robustness across multiple Windows versions and builds.
• Troubleshoot complex low-level issues, including kernel crashes, BSODs, race conditions, and performance bottlenecks.
• Contribute to automation and validation for driver and agent releases.

Your key objectives

• Build stable, high-performance kernel drivers
  : Develop reliable drivers validated across supported Windows versions.
• Strengthen agent self-protection
  : Implement advanced anti-tampering mechanisms and resistance to manipulation, with future ELAM support.
• Provide deep system visibility
  : Create accurate telemetry and interception across core OS subsystems.
• Advance low-level R&D
  : Evaluate and improve interception and monitoring techniques (minifilter, WFP, callbacks, ETW).
• Improve reliability & troubleshooting
  : Develop strong crash analysis, debugging, and automated regression testing capabilities.

Your profile
Hard skills

• Strong proficiency in C and low-level systems development.
• Solid understanding of Linux internals: memory management, scheduling, syscalls, namespaces, cgroups, kernel subsystems.
• Experience developing and maintaining kernel modules (LKM).
• Hands-on experience with eBPF (kprobes/uprobes, tracepoints, maps, CO-RE, BPF loaders).
• Experience building user-mode components interacting with low-level modules (netlink, ioctl, ring buffers, perf buffers, shared memory).
• Strong capability in debugging and troubleshooting kernel crashes, including BSOD and crash dump analysis, deadlocks, race conditions, IRQL issues, memory corruption and performance problems.
• Knowledge of network stack internals and system-level interception techniques.
• Experience with multiple Linux distributions (Debian, Ubuntu, RHEL/CentOS/Rocky, SUSE).
• Good understanding of secure coding practices, kernel hardening, and defense against kernel-level attacks.
• Experience with automated testing (CI/CD), kernel versioning, and validating features across multiple OS environments is a strong plus.

Soft skills

• Exceptional attention to detail and methodical approach.
• Strong analytical abilities and capacity to solve complex, low-level technical challenges.
• Autonomous, rigorous, and motivated by technical excellence.
• Collaborative mindset and willingness to support cross-team initiatives.
• Ability to follow structured processes while spotting opportunities for improvement.
• Strong documentation and reporting skills.
• Comfortable with technical English for documentation and research.

This role is for you if…

You thrive on low-level technical challenges and enjoy working deep inside OS internals.

You are autonomous, rigorous, and committed to delivering high-quality, production-grade code.

You have strong experience with Windows kernel development and want to push your expertise further.

You enjoy contributing to a fast-growing, mission-driven cybersecurity product.

This role is NOT for you if…

You are uncomfortable working in kernel-mode or low-level system environments.

You prefer highly structured environments over fast-paced, evolving technical contexts.

You avoid debugging complex issues, reverse engineering, or deep technical investigations.

You are not willing to take ownership or collaborate closely with cross-functional teams.

What we offer

• A unique technical environment at the intersection of OS internals, AI, and cybersecurity.
• The opportunity to contribute to a mission-critical, high-impact product used by organizations worldwide.
• A fast-moving, international, and collaborative team where ownership and initiative are valued.
• Benefits: Stock options program, hybrid/remote flexibility, continuous training and certification support, and more depending on profile.