Senior Software Engineer - Frontend

About the role

We are looking for a frontend engineer to own Mercari's web experience end to end. Beyond your own delivery, you are the frontend enabler for cross-platform engineers - Backend, iOS, Android, and QA - joining technical discussions and planning early so they can work AI-natively in web code instead of waiting on you.

What you'll do

• Own frontend delivery end to end: problem definition, AI-assisted prototyping, implementation, release, and production ownership — observability, rollback
• Build and evolve large-scale web applications with React and Next.js, owning rendering strategy, Core Web Vitals, and SEO for the buying and selling experience
• Act as the frontend specialist and enabler for cross-platform engineers (backend, iOS, Android, QA): review their web changes, pair with them, and set the patterns

What you need

• React
• HTML
• CSS
• JavaScript
• TypeScript
• Git

Good to have

• Design systems
• Test automation
• AWS
• Next.js
• Redux
• Jest