OS Scheduler Kernel Engineer

Apple • Cupertino, CA

9d

About The Position

The Darwin Scheduler team within Apple's Core OS organization is responsible for
the delivery of a high-quality and performant kernel for every Apple product.
Our software runs on your wrist in watchOS; in your pocket with iOS; on your
desk in macOS; and on the high-performance systems driving the creative
industry. The team focuses on key kernel technology areas such as CPU
scheduling, power management, and threading models which are central to
delivering industry-leading performance and battery life. We are looking for a
highly skilled Systems Engineer to join us in designing the next generation of
Apple’s kernel scheduler. As one of the few vertically integrated systems shops
remaining, our engineers have the unique opportunity to influence the entire
stack—from silicon design to the behavior of the world's most advanced
applications.

DESCRIPTION

As a Kernel Engineer on the Scheduler team, you will drive the evolution of the
XNU kernel to support the expanding capabilities of Apple Silicon. You will work
on the heart of the operating system, designing scheduling policies that balance
extreme performance with aggressive power efficiency. We are looking for a
self-driven engineer who thrives on navigating complex system interactions. You
will be responsible for identifying bottlenecks in highly parallel workflows,
optimizing the interaction between hardware and software, and ensuring our OS
scales gracefully from low-power embedded devices to massive high-performance
workstation architectures.

Requirements

• BS/MS/PhD in Computer Science, Computer Engineering, or equivalent experience.
• Fluency in C and C++
• Proven track record of debugging complex system issues (deadlocks, race conditions, performance regressions) and driving ambiguous problems to resolution.

Nice To Haves

• 5+ years of experience in Operating Systems development, with deep knowledge of kernel internals, and process/thread scheduling.
• Strong understanding of SMP/AMP architectures, synchronization primitives, lock-free algorithms, and cache coherency.

Responsibilities

• drive the evolution of the XNU kernel to support the expanding capabilities of Apple Silicon
• designing scheduling policies that balance extreme performance with aggressive power efficiency
• identifying bottlenecks in highly parallel workflows
• optimizing the interaction between hardware and software
• ensuring our OS scales gracefully from low-power embedded devices to massive high-performance workstation architectures

What This Job Offers

• Job Type: Full-time
• Career Level: Mid Level
• Education Level: Ph.D. or professional degree