Darwin Runtime Software Engineer (Core OS)

Quick Facts

• Role: Software Engineer, Darwin Runtime (Core OS)

• Focus: Low-level runtime technologies for Apple operating systems

Description

Darwin Runtime builds foundational low-level runtime technologies such as GCD, secure inter-process communication, memory allocation, threading libraries, and concurrency/synchronization primitives. The work sits at the intersection of operating systems, programming language design, systems security, and high-performance computing, partnering with kernel, security, and framework teams. The environment emphasizes autonomy, technical innovation, and technical ownership.

Responsibilities

• Design and implement new features and APIs for Darwin Runtime technologies like GCD, XPC, pthread, and malloc

• Design and implement IDL compiler frontend and backend systems (lexical analysis, parsing, semantic analysis, and code generation) for both C and Swift targets

• Develop and maintain high-performance runtime libraries for secure communication, memory management, and component lifecycle across different execution environments

• Optimize code generation, runtime performance, and memory usage to meet strict low-level system performance requirements

• Participate across the full software development lifecycle: problem definition, design, implementation, testing, and debugging

• Diagnose and resolve issues across different layers of the stack

• Collaborate with cross-functional teams to meet developer and product requirements

Requirements

• BS or MS in Computer Science or equivalent degree

• 0-3+ years of relevant industry experience in low-level systems programming

• Passion for low-level system technologies

• Fluency in C

• Experience with UNIX-like systems

• System design and architecture skills

• Strong understanding of operating system fundamentals (threading, synchronization primitives, inter-process communication, scheduling, virtual memory)

• Excellent collaboration skills for designing system architecture with a team

Benefits

• Technical innovation and meaningful ownership with a high level of autonomy

• Opportunities to build foundational technologies for next-generation Apple computing platforms