Apple

Apple

Posted via Apple Careers

JavaScript Virtual Machine Compiler Engineer

Always Hiring

Posted Aug 4, 2026

Role at a glance

Salary
$150.4K – $277.6K/yr
Location
Cupertino, California, United States
Work arrangement
On-site
Employment
Full-time
Education
BS in computer science or equivalent

Spotted an issue?

We’ll check it against the original posting.

Log in to report

Role Summary

AI-generated

The JavaScriptCore team in WebKit develops the JavaScriptCore engine to make JavaScript and WebAssembly execution fast and secure across Apple products. The role focuses on improving the engine’s JIT compilers, runtime systems, garbage collector, compatibility, performance, security, and stability.

What You'll Do

  • Improve JavaScriptCore’s JIT compilers, runtime systems, and garbage collector
  • Work across the engine’s compilation pipeline, language runtime, garbage collector, and native app API
  • Drive new innovations and add new optimizations
  • Tune performance and implement language features
  • Diagnose and fix existing problems
  • Help guide the evolution of JavaScript and WebAssembly languages via public standards

Generated from the employer's posting. Verify important details before applying.

View full posting

Qualifications

BS in computer science or equivalent; experience programming in modern C++; experience with compilers, parsers, interpreters, assembly-level programming, performance analysis, memory allocators, and garbage collectors; excellent debugging, critical thinking, and communication skills.

Required

  • 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

Preferred

  • 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

Original job description

Content provided by the employer

Summary

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.

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

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

Pay & Benefits — Cupertino, California, United States

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 $150,400 and $277,600, 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.

Application Deadline

Apple accepts applications to this posting on an ongoing basis.

Apple

About the company

Apple

Large Enterprise

Apple Inc. is a global technology company known for its innovative products and services, including the iPhone, iPad, Mac computers, and Apple Watch. Founded in 1976, Apple has continuously pushed the boundaries of design and functionality, earning a reputation for high-quality consumer electronics and software solutions like iOS and macOS. With a strong commitment to user experience and privacy, Apple also leads in digital services, offering platforms such as the App Store, Apple Music, and iCloud. The company's focus on sustainability and corporate responsibility further enhances its standing as a leader in the technology sector.