macOS Endpoint Security Engineer

Role

Senior macOS Cyber Security Engineer, Endpoint Security (C++/Swift)

Location

Remote (PST working hours)

Client

Accenture/Amazon

Work Authorization

U.S. Citizen (USC) or Green Card (GC) holders only

Requirement Type

Contractual

Experience

6-10 years, we can evaluate more senior as well but need to build a pyramid.

W-2 Rate

$65 - $70/hr.

Job Description

About the workYou'll work on the macOS sensor for CrowdStrike Falcon, an on-device security agent. It monitors file, process, network and identity activity, blocks malicious behavior, and streams telemetry to the cloud. The sensor runs entirely in user space as a System Extension. Much of the code is shared with Windows and Linux. The work requires high concurrency, high reliability, careful attention to memory & CPU usage and performance.

Required

Languages

modern C++ (C++17/20) and Swift 6 (async/await, actors, strict concurrency checking). Also Objective-C++ to bridge Swift, C++ and C APIs.

macOS systems programming

Foundation and CoreFoundation, GCD and pthreads, POSIX/BSD APIs, Mach IPC, launchd daemons and agents, and XPC (C API and NSXPCConnection).

Performance, debugging and test

o Profiling CPU and memory with Instruments and os_signpost.

o Debugging with LLDB, crash logs and os_log.

o XCTest, sanitizers, fuzzing, and xcodebuild-based CI.

o Apple Silicon and Intel.

• Experience with codebases shared across Mac, Windows and Linux.

Core skills (one or more of the areas listed below)

Process model and IPC

launchd daemons and agents, and XPC (C API and NSXPCConnection).

Endpoint Security and System Extensions

Endpoint Security clients handling both blocking (AUTH) events and notification events, user/MDM approval, upgrades.

Network Extension

content filters, both flow-level (NEFilterDataProvider) and packet-level (NEFilterPacketProvider), and Network.framework.

Security and crypto

Verifying code signatures (SecCode / SecStaticCode) and validating certificates (SecTrust), Keychain, Entitlements, hardened runtime, and macOS privacy permissions.

Devices and storage

IOKit (hardware and device enumeration) and DiskArbitration (disk and volume events).

Packaging and deployment

installers, notarization, and MDM configuration profiles deployed through Jamf, Intune or similar tools.

Performance, debugging and test

Profiling CPU and memory with Instruments and os_signpost, Debugging with LLDB, crash logs and os_log, XCTest, sanitizers, fuzzing, and xcodebuild-based CI.

Nice to have

UI

SwiftUI and AppKit apps and app extensions.

• Testing against macOS and Xcode betas before public release.
• Experience shipping EDR/AV, network security or device-management products.