OS Kernel Engineer

As a junior OS Kernel Engineer on the Darwin Scheduler team, you will work alongside experienced engineers to learn, contribute, and grow your skills in low-level systems programming. You will be supported through mentorship and paired work as you begin to take on real-world kernel engineering challenges across Apple's platforms.

This is an exceptional opportunity for someone who is passionate about systems software, eager to understand how hardware and software interact, and excited to write code that runs on hundreds of millions of devices.

Learn and Contribute to Scheduling Policies: Assist in developing and validating CPU scheduling policies that balance performance with power efficiency across Apple's product lines.

Performance Analysis: Work with senior engineers to analyze system performance, identify bottlenecks, and understand tradeoffs between hardware capabilities and OS behavior.

Cross-Platform Development: Contribute to shared scheduling concepts and code that run across iOS, macOS, watchOS, and tvOS, learning how a unified kernel serves vastly different device classes.

Tooling and Benchmarking: Help build and maintain benchmarks and diagnostic tools used to validate scheduler behavior and support engineering decisions.

Workload Management: Participate in the design and implementation of features that manage diverse workloads to maximize responsiveness and efficiency.

Debugging and Investigation: Learn to diagnose and resolve concurrency and scheduling issues under the guidance of experienced engineers.

Collaboration: Work closely with hardware and silicon teams, contributing to the cross-functional work that makes Apple's vertical integration a competitive advantage.

BS in Computer Science, Computer Engineering, Electrical Engineering, or equivalent (graduating or recently graduated)

Coursework or project experience in operating systems, systems programming, or computer architecture

Proficiency in C and/or C++

Solid understanding of fundamental computer science concepts: data structures, algorithms, and memory management

Strong analytical and problem-solving skills

Eagerness to learn and ability to ramp up quickly on complex technical topics

MS or PhD in Computer Science or a related field

Coursework or hands-on experience with OS internals, scheduling algorithms, or concurrency

Familiarity with SMP (symmetric multiprocessing), threading models, or lock-free data structures

Experience with performance profiling tools or low-level debugging

Contributions to open-source OS or systems projects

Internship or research experience in systems software

The Darwin Scheduler team within Apple's OS organization is responsible for delivering a high-quality and performant kernel that powers every Apple product — from Apple Watch on your wrist, to iPhone in your pocket, to the Mac driving the creative industry. We work on foundational technology areas such as CPU scheduling, power management, and threading models that are central to everyday life for billions of people.

We are looking for a talented new graduate or junior engineer to join us and contribute to the next generation of Apple's operating system. As a member of a small, technically integrated team, you will have a unique opportunity to influence the entire stack — from silicon behavior to user experience — on the world's most advanced and widely used devices.

At Apple, base pay is one part of our total compensation package and is determined within a range. This provides the opportunity to progress as you grow and develop within a role. The base pay range for this role is between $126,800 and $220,900, and your base pay will depend on your skills, qualifications, experience, and location.

Apple employees also have the opportunity to become an Apple shareholder through participation in Apple’s discretionary employee stock programs. Apple employees are eligible for discretionary restricted stock unit awards, and can purchase Apple stock at a discount if voluntarily participating in Apple’s Employee Stock Purchase Plan. You’ll also receive benefits including: Comprehensive medical and dental coverage, retirement benefits, a range of discounted products and free services, and for formal education related to advancing your career at Apple, reimbursement for certain educational expenses — including tuition. Additionally, this role might be eligible for discretionary bonuses or commission payments as well as relocation. Learn more about Apple Benefits

Note: Apple benefit, compensation and employee stock programs are subject to eligibility requirements and other terms of the applicable plan or program.

Apple is an equal opportunity employer that is committed to inclusion and diversity. We seek to promote equal opportunity for all applicants without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, Veteran status, or other legally protected characteristics. Learn more about your EEO rights as an applicant

At Apple, we believe accessibility is a fundamental human right. You’ll find that idea reflected in everything here — in our culture, our benefits and our digital tools. By welcoming as many perspectives as possible, we help you build a career where you feel like you belong.

Learn about accessibility in Apple’s workplace

Learn about reasonable accommodations for job applicants

Apple accepts applications to this posting on an ongoing basis.