Mobile Engineer

Juno (YC P26); Greater London; On-site; GBP 65,000 - 100,000; Full time

Job summary

Juno (YC P26) is building its mobile product and seeks a Mobile Engineer to take ownership of features from prototype to release. You will ship with React Native, Expo, and TypeScript, shaping the user experience and performance.

You’ll work closely with the founder to translate ideas into tangible improvements for real users across iOS and Android, delivering polished interfaces and reliable releases in a fast-moving startup.

Qualifications

• Shipping mobile apps used by real customers.
• Strong React Native and TypeScript skills with Expo.
• Understanding of iOS and Android releases, debugging, and performance.

Responsibilities

• Build and ship features with React Native, Expo, and TypeScript.
• Create fast, intuitive interfaces with careful attention to design and detail.
• Improve performance, reliability, and the quality of every release.
• Own features end to end: implementation, testing, release, and iteration.
• Work closely with the founder to turn product ideas into real improvements for users.

Skills

React Native

TypeScript

Expo

Performance optimization

App deployment

Communication

Tools

Xcode

Android Studio

Job description

Build the mobile experience that defines Juno.

Juno (YC P26) is hiring a Mobile Engineer to help turn ambitious ideas into a polished product people love using. If you care as much about how an app feels as how it works—and you love shipping—this is your opportunity to make a visible impact.

THE ROLE

Take ownership of mobile features from the first prototype to release. Help shape the product, make thoughtful engineering decisions, and turn user feedback into better experiences across iOS and Android.

WHAT YOU’LL DO

• Build and ship features with React Native, Expo, and TypeScript.
• Create fast, intuitive interfaces with careful attention to design and detail.
• Improve performance, reliability, and the quality of every release.
• Own features end to end: implementation, testing, release, and iteration.
• Work closely with the founder to turn product ideas into real improvements for users.

WHAT YOU’LL BRING

• Experience shipping and maintaining mobile apps used by real customers.
• Strong React Native and TypeScript skills, with experience in Expo.
• An understanding of iOS and Android releases, debugging, and performance.
• Product judgement, clear communication, and the initiative to move work forward.
• Evidence of what you’ve built: an app link, a portfolio, or a short explanation of your contribution.

A BIG PLUS

You’ve helped build or scale an app to $100k+ in monthly recurring revenue (MRR). Tell us what you owned and how your work contributed. This is a bonus, not a requirement.

WHY JUNO

• Meaningful ownership of the mobile product and the decisions behind it.
• The opportunity to shape an early-stage product and see your work reach users.
• Ambitious problems, short feedback loops, and plenty to build.