macOS Endpoint Security Engineer

Accountabilities:: Develop, enhance, and maintain macOS endpoint security components using modern C++ (C++17/C++20), Swift 6, and Objective-C++. Contribute to the development of an endpoint security sensor that monitors file, process, network, and identity activities, blocks malicious behavior, and transmits security telemetry. Implement and maintain macOS System Extensions and Endpoint Security clients, including authorization (AUTH) events, notification events, user and MDM approval workflows, and extension upgrades. Develop and optimize system-level components using Foundation, CoreFoundation, Grand Central Dispatch (GCD), pthreads, POSIX/BSD APIs, Mach IPC, launchd, and XPC. Build and maintain network security capabilities using Network Extensions, including flow-level and packet-level content filtering, and Network.framework. Implement security mechanisms involving code-signature verification, certificate validation, Keychain, entitlements, hardened runtime, and macOS privacy permissions. Support hardware and storage-related functionality through IOKit and DiskArbitration. Optimize application performance, concurrency, CPU utilization, and memory consumption to ensure high reliability and minimal system overhead. Investigate and resolve complex technical issues using Instruments, os_signpost, LLDB, crash logs, and os_log. Develop and maintain automated tests using XCTest, sanitizers, fuzz testing, and xcodebuild-based continuous integration pipelines. Ensure software compatibility across Apple Silicon and Intel-based Mac systems. Collaborate with cross-platform engineering teams to maintain shared codebases supporting macOS, Windows, and Linux. Contribute to application packaging, installation, notarization, and deployment through MDM solutions such as Jamf and Microsoft Intune. Support software quality, secure development practices, and production reliability throughout the development lifecycle. Requirements: 6–10 years of professional software engineering experience, with consideration for more senior candidates. Strong proficiency in modern C++, particularly C++17/C++20, and Swift 6, including async/await, actors, and strict concurrency checking. Hands-on experience with Objective-C++ and integrating Swift, C++, and C APIs. Strong macOS systems programming knowledge, including Foundation, CoreFoundation, GCD, pthreads, POSIX/BSD APIs, and Mach IPC. Experience with launchd daemons and agents, XPC C APIs, and NSXPCConnection. Practical experience in at least one or more of the following areas: Endpoint Security and System Extensions: Endpoint Security clients, authorization and notification events, extension approvals, MDM integration, and upgrades. Network Security: Network Extension content filters, NEFilterDataProvider, NEFilterPacketProvider, and Network.framework. Process Management and IPC: launchd services, daemons, agents, and XPC communication. Security and Cryptography: SecCode, SecStaticCode, SecTrust, Keychain, entitlements, hardened runtime, and macOS privacy permissions. Devices and Storage: IOKit, hardware and device enumeration, DiskArbitration, and disk or volume event handling. Packaging and Deployment: macOS installers, application notarization, and MDM configuration profiles through Jamf, Intune, or similar platforms. Strong experience with performance profiling and debugging tools, including Instruments, os_signpost, LLDB, crash logs, and os_log. Familiarity with XCTest, sanitizers, fuzz testing, and xcodebuild-based CI workflows. Experience developing and maintaining large, shared codebases across macOS, Windows, and Linux. Understanding of operating-system internals, concurrency, memory management, and performance-sensitive software development. Ability to troubleshoot complex technical problems and deliver reliable, maintainable solutions. Strong analytical, problem-solving, and collaboration skills, with the ability to work effectively in a distributed engineering environment. Additional experience with SwiftUI, AppKit, application extensions, and testing against macOS or Xcode beta releases is advantageous. Previous experience developing and shipping endpoint detection and response (EDR), antivirus (AV), network security, or device-management products is highly desirable. Must be a U.S. citizen or Green Card holder. Must be available to work remotely during Pacific Standard Time (PST) business hours. Benefits: Competitive compensation: Hourly W-2 contract rate of $65–$70. Remote flexibility: Fully remote working arrangement within the United States. Technical challenges: Opportunity to work on sophisticated endpoint security and cybersecurity technologies. Professional growth: Exposure to advanced macOS systems programming, operating-system internals, and cross-platform software engineering. Industry impact: Contribute to the development of security solutions designed to protect enterprise devices against evolving cyber threats. Collaborative environment: Work alongside experienced engineers on complex, large-scale technical projects. Specialized expertise: Strengthen your knowledge of endpoint protection, network security, and high-performance systems development.