Overview
GitHub is changing the way the world builds software, and we want you to help. We're looking for a Senior Software Engineer to join the Core UX organization and contribute to the foundation of GitHub's UI platform.

More of the world's development data lives on GitHub than anywhere else. Helping developers navigate, understand, and collaborate on that data is a core part of our mission. At the heart of these efforts is a growing React-based platform, shared UI components, and foundational infrastructure that enables product engineers to ship accessible, performant, and scalable UI by default.

This role sits at the intersection of frontend architecture, performance, and developer experience. You will work on modernizing GitHub's web UI, evolving the React application framework, improving Core Web Vitals across key user flows, and building platform-level solutions (state management, error handling, navigation, lazy loading) that product teams rely on daily. Your work will directly impact the speed, reliability, and quality of GitHub's product experience for millions of developers.

We're looking for someone with deep expertise in React, frontend architecture, and performance who has demonstrated an ability to modernize complex, large-scale web applications with measurable results.

Responsibilities-
Contribute to the architectural design and evolution of GitHub's React platform, with a focus on performance, scalability, and developer experience

• Help drive the migration of key UI surfaces from Rails server-rendered views to modern React-based patterns, including the ongoing UI Service initiative

• Identify and resolve frontend performance bottlenecks across page load (LCP), interaction latency (INP), and layout stability (CLS)

• Build platform-level primitives and patterns (state management, error handling, data fetching, lazy loading) that enable feature teams to ship faster with fewer mistakes

• Collaborate with design system, accessibility, and infrastructure teams to ensure platform changes meet cross-cutting quality standards

• Contribute to architectural decision-making for the frontend platform, including rendering strategies, build tooling, and framework evolution

• Produce technical proposals and design documents for cross-team initiatives

• Support and mentor engineers across the organization on modern frontend architecture and performance best practices

• Participate in code reviews to ensure quality, consistency, and adherence to platform patterns across a large, multi-team codebase

Qualifications:

Required/Minimum Qualifications:

• 9+ years experience in Software Engineering, Computer Science, or related technical discipline with proven experience maintaining and delivering production software coding in languages including, but not limited to, C, C++, C#, Java, JavaScript, Go, Ruby, Rust, or Python

OR Associate's Degree in Computer Science, Electrical Engineering, Electronics Engineering, Math, Physics, Computer Engineering, Computer Science, or related field AND 5+ years experience in Software Engineering, Computer Science, or related technical discipline with proven experience maintaining and delivering production software coding in languages including, but not limited to, C, C++, C#, Java, JavaScript, Go, Ruby, Rust, or Python

• OR Bachelor's Degree in Computer Science, Electrical Engineering, Electronics Engineering, Math, Physics, Computer Engineering, Computer Science, or related field AND 4+ years experience in Software Engineering, Computer Science, or related technical discipline with proven experience maintaining and delivering production software coding in languages including, but not limited to, C, C++, C#, Java, JavaScript, Go, Ruby, Rust, or Python

• OR Master's Degree in Computer Science, Electrical Engineering, Electronics Engineering, Math, Physics, Computer Engineering, Computer Science, or related field AND 2+ years experience in Software Engineering, Computer Science, or related technical discipline with proven experience maintaining and delivering production software coding in languages including, but not limited to, C, C++, C#, Java, JavaScript, Go, Ruby, Rust, or Python

• OR Doctorate in Computer Science, Electrical Engineering, Electronics Engineering, Math, Physics, Computer Engineering, Computer Science, or related field

• OR equivalent experience

• 6+ years of experience working with React, TypeScript, CSS, and frontend tooling (e.g., Webpack, Vite, ESLint, Jest)

• 6+ years of experience building frontend applications using React-based frameworks or libraries (e.g., Next.js, Remix, Tan Stack Router/Query)

Preferred Qualifications:

• Experience with frontend platform or infrastructure work (application frameworks, build systems, shared libraries)

• Experience migrating legacy frontend architectures to modern patterns at scale

• Experience with server-side rendering, streaming, and hybrid rendering strategies

• Familiarity with design systems or component library development

• Extensive experience with TypeScript in large codebases

• Prior experience with Ruby on Rails or other server-side frameworks

• Experience navigating how different concerns within the frontend space overlap (accessibility, performance, UX consistency) and crafting execution strategies that account for all of them

• Strong understanding of web performance fundamentals (Core Web Vitals, rendering pipelines, JavaScript execution cost, network optimization)

• Excellent written and verbal communication skills

Ability to meet Microsoft, customer and/or government security screening requirements are required for this role. These requirements include, but are not limited to the following specialized security screenings:

Microsoft Cloud Background Check: This position will be required to pass the Microsoft Cloud Background Check upon hire/transfer and every two years thereafter.

This position will be open for a minimum of 5 days, with applications accepted on an ongoing basis until the position is filled.

Microsoft is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to age, ancestry, citizenship, color, family or medical care leave, gender identity or expression, genetic information, immigration status, marital status, medical condition, national origin, physical or mental disability, political affiliation, protected veteran or military status, race, ethnicity, religion, sex (including pregnancy), sexual orientation, or any other characteristic protected by applicable local laws, regulations and ordinances. If you need assistance with religious accommodations and/or a reasonable accommodation due to a disability during the application process, read more about requesting accommodations.