Senior MacOS Internals Lead Engineer

Our client is a US based security company looking for a Senior macOS Internals Lead Engineer to drive the development of lowlevel security and compatibility functionality. You will lead a team of exceptional engineers while remaining deeply handson—writing code, reverse engineering OS behavior, and directly owning key systemlevel components.

Your team’s mission is to expand macOS application compatibility and harden endpoint security by deeply understanding and integrating with macOS internals. This role is ideal for someone who thrives on technical challenges, understands macOS at a deep level, is not afraid of reverse engineering and can mentor others while shipping production code.

What You Will Do:

1. Design and implement security features using macOS frameworks such as Endpoint Security and Network Extensions.
3. Reverse engineer macOS internals and application interactions to enhance product compatibility and security.
5. Develop, debug, and optimize complex systemlevel code in C++, Swift, and ObjectiveC, adhering to secure coding best practices.
7. Investigate and resolve issues related to macOS system extensions, launch services, XPC, and sandboxing.
9. Act as a force multiplier by reviewing team designs and code, offering architectural direction, and coaching team members on best practices.
11. Document technical findings, architectural designs, and implementation details
13. Collaborate with QA, product, and support teams to ensure highquality, secure, and testable deliverables.
15. Stay updated on macOS updates and security mechanisms in order to inform development.

16. Requirements

    1. 7+ years of systems programming experience with a focus on macOS internals, frameworks, and security
    3. Proven track record of delivering complex macOS features to productions with hands on coding in C++, Swift, ObjectiveC
    5. Deep expertise in macOS frameworks, including Endpoint Security, Network Extensions, Accessibility, Launch Services, File Providers, daemons, XPC and FSEvents
    7. Advanced skills in reverse engineering MacOS components using tools like Ghidra, Frida,IDA, Hopper, lldb or other tools of your choice. You’re not afraid to look at XNU sources.
    9. Strong understanding of macOS security mechanisms, including TCC, SIP, Gatekeeper.
    11. Experience with debugging complex architectures on MacOS (system extensions, endpoint security, network extensions, launch services, XPC).
    13. Ability to produce highquality, testable, maintainable and secure code

    14. Nice to have:

        1. Expertise with Network Extensions, DriverKit, network protocols, proxies.
        3. Expertise with APFS, file system internals.
        5. C# .Net experience is a plus.

        6. Benefits

           Salary: $10,000 $15,000 USD month + Holidays

           Unlimited PTO