Principal Software Engineer, Front End Web UI Platform

GitHub's Core UX organization owns the frontend platform behind GitHub.com: the architecture, tooling, and standards that let hundreds of engineers ship UI that is fast, accessible, consistent, and reliable.

We're looking for a Principal Software Engineer to set technical direction across that platform and raise the ceiling on what the frontend can do for millions of developers.

This is a systems role, not a single-team role.

You'll work across the concerns that overlap in frontend at scale: performance, accessibility, UX consistency, and availability.

Much of the work is evolving a large, actively developed codebase rather than starting from scratch, so success depends as much on migration strategy and cross-team alignment as on architecture.

You'll shape paved paths that many teams adopt, not one-off solutions that rely on heroics.

You'll partner closely with other Principal and Staff engineers, Engineering Managers, and Product and Design leadership to decide where the platform goes next and to drive that direction to real, shipped outcomes.

• Own the technical direction for GitHub's web UI platform across performance, accessibility, consistency, and availability, balancing long-term architecture with hands-on execution.
• Drive large cross-team initiatives and migrations, sequencing the work so the platform moves forward without disrupting active product development.
• Establish patterns, standards, and paved paths for frontend development that lower cognitive load and scale across many teams.
• Produce architecture and design proposals, evaluate tradeoffs honestly, and build alignment across engineering, product, and design.
• Mentor and raise the bar for engineers at every level through design review, code review, and pairing.
• Represent frontend platform priorities to leadership, securing the support and resourcing needed to deliver.

What Success Looks Like in the First 6 Months

• You've built a deep working understanding of GitHub's frontend systems, infrastructure, and their backend dependencies, and you're using it to make informed, high-leverage decisions.
• You're leading at least one platform-wide initiative that measurably improves performance, availability, frontend infrastructure, or developer velocity.
• Teams are adopting the patterns and paved paths you've shaped, with less need for direct hand-holding.