React Native Developer; Mid–Senior

About Us

Ruby Labs is a leading tech company that creates and operates innovative consumer products. We offer a diverse range of opportunities across the health, education, and entertainment industries. Our innovative teams are driving the future of consumer‑led products, and we’re always looking for passionate individuals to join us. Learn more about our story at:

At Ruby Labs, we’re looking for a React Native Developer (Mid–Senior) to join our growing engineering team as we expand into mobile. This is a high‑impact role for an engineer who enjoys shipping real product features, solving performance challenges, and building clean, scalable applications for iOS and Android.

You’ll collaborate closely with backend, product, and design teams while owning meaningful parts of the mobile codebase and helping deliver a fast, reliable, and polished experience to our users.

• Deliver new mobile product features with strong execution and attention to detail.
• Maintain and improve the React Native codebase, performance, and stability.
• Integrate with backend APIs, caching layers, and real‑time services.
• Debug production issues, investigate edge cases, and ship fixes quickly.
• Implement crash reporting and performance observability (Sentry, tracing, logs, metrics).
• Optimize app performance across rendering, navigation, memory usage, latency, and offline behavior.
• Write clean, maintainable code with a strong understanding of software fundamentals.
• Contribute to technical discussions, planning, documentation, and delivery decisions.
• Support improvements to builds, releases, testing, and app store deployments.

• 3–5+ years of experience building mobile applications.
• Strong production experience with React Native.
• Deep understanding of React fundamentals (hooks, context, component lifecycle, rendering behavior).
• Experience working with native modules and iOS/Android bridging when needed.
• Experience shipping and maintaining apps on the App Store and Google Play.
• Experience with mobile builds, releases, CI/CD, or OTA update flows (EAS, Code Push, or similar).
• Experience with crash reporting and observability tools (e.g., Sentry, performance tracing, logs).
• Strong grasp of software development fundamentals and best practices.
• Ability to debug and fix issues confidently in production.
• Comfortable owning features or technical components with autonomy.
• Demonstrates accountability for edge cases, reliability, and user experience.
• Passionate about building scalable, reliable products that users depend on.

• Experience working in startup or high‑ownership product teams.
• Experience improving performance, automating releases, or enhancing mobile reliability at scale.
• Familiarity with backend services (Node.js, AWS, Redis, Cloudflare) to enable seamless API integration.
• Experience contributing to or building mobile design systems or shared component libraries.
• Experience with real‑time mobile data flows (Web Sockets, streaming, event ingestion).

Ruby Labs operates within the CET (Central European Time) zone. Applicants from any country are welcome to apply for the position as long as they are located within approximately ± 4 hours of CET. This ensures optimal collaboration and communication during working hours.

• Remote Work Environment:
  Embrace the freedom to work from anywhere, anytime, promoting a healthy work‑life balance.
• Unlimited PTO:
  Enjoy unlimited paid time off to recharge and prioritize your well‑being, without counting days.
• Paid National Holidays:
  Celebrate and relax on national holidays with paid time off to unwind and recharge.
• Company‑provided Mac Book:
  Experience seamless productivity with top‑notch Apple Mac Books provided to all employees who need them.
• Flexible Independent Contractor Agreement:
  Unlock the benefits of flexibility, autonomy, and entrepreneurial opportunities. Benefit from tax advantages, networking opportunities, reduced employment obligations, and the freedom to work from anywhere. Read more about it here:

• Recruiter Screening (40 minutes)
• First Interview (30 minutes)
• Technical Interview (45 minutes)
• Final Interview (30 minutes)