Senior Full Stack Engineer (Web-first, Cross-Platform)

Gametime United is focused on uniting the world through shared live experiences, making it easier for people to discover and access events. They are seeking a Senior Full Stack Engineer to enhance web performance and user experiences, primarily through React development, while contributing to cross-platform features and improving Core Web Vitals.

Responsibilities:

• Build and ship production features in React (legacy SPA) with TypeScript
• Contribute to our Astro-based static and mixed-rendering architecture
• Implement performance optimizations that improve Core Web Vitals (LCP, CLS, INP)
• Apply technical SEO best practices within features (rendering behavior, metadata, structured data, crawl-safe patterns)
• Work within SSR, SSG, and hydration constraints — understanding tradeoffs and execution details
• Contribute to shared features in React Native when functionality overlaps with web
• Move features cross-platform when appropriate rather than relying on handoffs
• Collaborate with mobile engineers on platform-specific adjustments
• Contribute to performance-sensitive areas, including occasional native integrations as our tooling evolves
• Use AI agents for component generation, test writing, and performance optimization — our mixed-rendering architecture involves a lot of SSR/SSG scaffolding and rendering validation that benefits from agentic coding
• Participate in code reviews and architectural discussions
• Ship iteratively with a strong bias toward measurable performance impact

Requirements:

• 3+ years building production web applications in React and TypeScript
• Strong understanding of rendering models (CSR, SSR, SSG, hydration)
• Experience working on performance-sensitive surfaces
• Working knowledge of Core Web Vitals and frontend performance fundamentals
• Familiarity with technical SEO concepts (indexability, structured data, crawl behavior)
• Comfort navigating existing codebases and shipping independently
• Experience directing AI agents for frontend-specific work (rendering strategies, SEO patterns, Core Web Vitals optimization) is a strong signal
• Willingness to work across web and mobile surfaces when needed
• Experience with React Native
• Experience with Astro or other mixed-rendering frameworks (Next.js, Remix, etc.)
• Exposure to native iOS or Android development
• Marketplace, e-commerce, or high-traffic consumer product experience
• Experience working in experimentation-heavy environments
• Familiarity with using EdTest