Principal UI Engineer: Real-Time Collaboration Platform

Yahoo Holdings Inc.; New York (NY); Hybrid; USD 180,000 - 300,000; Full time

Benefits offered by this job

Flexible hybrid work

Job summary

Yahoo Holdings Inc. is seeking a seasoned Principal Engineer to lead platform architecture and real-time collaboration systems at scale in a hybrid New York setting. You will own critical infrastructure, CRDT-based multi-user editing, and AI tooling interfaces, while mentoring engineers and aligning cross-functional teams.

You will drive performance, observability, and secure design across UI and backend components, shaping the engineering standards and roadmaps for the organization.

Qualifications

• 8+ years of experience designing, building, and operating production-scale web platforms.
• Advanced mastery of modern TypeScript, JavaScript, React, and server-side runtimes (Node.js or Bun).
• Hands-on experience with real-time data models, WebSockets, and collaborative editing (CRDTs such as Yjs or Automerge, or OT).
• Strong SQL and PostgreSQL foundations, including schema evolution and access-control patterns.

Responsibilities

• Own the architecture, scalability, and uptime of our real-time collaboration server, Postgres-backed persistence layer, background jobs, and the APIs that sit on top of them.
• Design, harden, and evolve multi-user editing built on CRDTs (Yjs). Guarantee reliable sync, reconnection, conflict handling, undo/redo, and save durability.
• Architect and maintain agent-ready interfaces, Model Context Protocol (MCP) servers, and automated pipelines for AI agents and developers.
• Profile and optimize end-to-end bottlenecks: interactive canvas rendering, frame rates, hydration and bundle payloads, query cost, memory footprint, and server health.
• Steer the evolution of our large TypeScript monorepo, CI/CD pipelines, automated testing, and environments to keep shipping fast and reproducible.
• Define SLOs, metrics, structured logging, and real-time alerting; lead blameless post-incident reviews and durable fixes.
• Partner on authentication, authorization, and permission models across systems, branches, and files.
• Contribute to product UI in React and TypeScript where performance and data flow matter most.
• Set standards for AI workflow, code review, and testing for accuracy and security across lifecycles.
• Mentor staff and senior engineers, lead architecture reviews, and align roadmaps across teams.

Skills

TypeScript

React

Node.js

WebSockets

CRDTs

PostgreSQL

Performance optimization

Mentoring

CI/CD

AI tooling

Tools

Yjs

Automerge

Turborepo

Nx

Playwright

Jest

Redis

Job description

Yahoo Holdings Inc. is seeking a seasoned Principal Engineer to lead platform architecture and real-time collaboration systems at scale in a hybrid New York setting. You will own critical infrastructure, CRDT-based multi-user editing, and AI tooling interfaces, while mentoring engineers and aligning cross-functional teams.

You will drive performance, observability, and secure design across UI and backend components, shaping the engineering standards and roadmaps for the organization.