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Darwin Runtime Engineer, Core OS

Cupertino, United States of America💼 Full-time🗓 2026-08-20 → 2026-09-28

Core

Design and implement low-level runtime technologies (GCD, XPC, pthread, malloc) and compiler frontend/backend systems for Apple's operating systems.

Role type

Senior IC systems software engineer (runtime & compiler)

Builds

Foundational runtime libraries, secure IPC systems, and compiler toolchains for iOS, macOS, watchOS, and tvOS

Domain

Operating systems, systems security, high-performance computing

Required skills

C programming, UNIX-like systems, OS fundamentals (threading, synchronization, IPC, scheduling, virtual memory), system design, low-level systems programming

Preferred skills

Compiler design (lexical analysis, parsing, code generation), capability-based security models, Swift/Objective-C, assembly programming, debugging tools (lldb/gdb)

Technologies

GCD, XPC, pthread, malloc, C, Swift, Objective-C, UNIX

Responsibilities

Design and implement new features and APIs for Darwin Runtime technologies; Develop and maintain high-performance runtime libraries; Optimize code generation, runtime performance, and memory usage; Diagnose and resolve issues across different layers of the stack

Seniority

Mid-level to Senior, hands-on IC

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