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JavaScript Virtual Machine Compiler Engineer

Today Cupertino, CA

In this role, you have the opportunity to push the state of the art of JavaScript and WebAssembly performance. The JavaScriptCore team at Apple is looking for system programmers with compiler (especially just-in-time) and virtual machine experience. You will be working to deliver a faster and more secure web for all Apple products by improving JavaScriptCore's already world-class JIT compilers, runtime systems, and the garbage collector. The work is challenging, and the impact is worldwide. Join us.

Description

The JavaScriptCore team in WebKit is responsible for the JavaScriptCore engine, and our mission is to make JavaScript and WebAssembly execution both fast and secure. JavaScriptCore engineers work on all aspects of the engine: the compilation pipeline, the language runtime, the garbage collector, and the API for native apps. The compilation pipeline consists of the parser, the bytecode frontend, profile-guided type profiling, and multiple optimizing compiler backend that turn JS and Wasm programs into efficient ARM and x86 machine code.

In this role, you will work across all areas of the engine, improving the performance, security, and stability of the engine, as well as compatibility with other browsers. You will also help guide the evolution of the JavaScript and WebAssembly languages via public standards. You will drive new innovations, add new optimizations, tune performance, implement language features, in addition to diagnosing and fixing existing problems.

Preferred Qualifications

Hands-on experience with VMs with just-in-time compilers (e.g. JavaScript engines and JVMs)

Experience with web browsers

Knowledge of JavaScript and WebAssembly

Minimum Qualifications

BS in computer science or equivalent

Experience programming in modern C++

Excellent debugging, critical thinking, and communication skills

Experience with compilers, parsers, and interpreters

Experience with assembly-level programming

Experience with performance analysis

Experience with memory allocators and garbage collectors

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 .

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Client-provided location(s): Cupertino, CA
Job ID: apple-200631874-0836_rxr-658
Employment Type: OTHER
Posted: 2025-11-16T19:09:07

Perks and Benefits

  • Health and Wellness

    • Parental Benefits

      • Work Flexibility

        • Office Life and Perks

          • Vacation and Time Off

            • Financial and Retirement

              • Professional Development

                • Diversity and Inclusion

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