Apple
Darwin Runtime Engineer, Core OS
$150K–$278K
Cupertino, California · Full-time · Posted Oct 26, 2026
- Experience
- 6+ years of experience with UNIX-like systems.
- Education
- BS or MS in Computer Science or equivalent degree.
About the job
Develops and evolves low-level Darwin Runtime libraries and APIs that support Apple operating systems, with a focus on performance, memory management, and system reliability.
What you'll do
- Design, implement, and maintain features and APIs for runtime technologies such as GCD, XPC, pthread, and malloc.
- Optimize runtime performance, code generation, and memory use; diagnose and resolve issues across system layers.
- Participate in the software development lifecycle, including design, implementation, testing, and debugging, and collaborate across teams.
What they ask for
- Fluency in C.
- 6+ years of experience with UNIX-like systems.
- System design and architecture skills, plus a strong understanding of operating system fundamentals including threading, synchronization, IPC, scheduling, and virtual memory.
- BS or MS in Computer Science or equivalent degree.
Nice to have
- Knowledge of operating system implementation, hardware architecture, and assembly programming; knowledge of Swift or Objective-C.
- Experience with lldb or gdb; experience using Gen AI tools for software development; interface or API design skills.
Pay
$150,400 to $277,600 USD base salary
Tools
C, Grand Central Dispatch (GCD), XPC, pthread, malloc, Swift, Objective-C, lldb
AI focus
Experience using Gen AI tools for software development is preferred; no other AI work is stated.
Model-written summary · the original posting is authoritative