Lead React Native Developer

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 Lead React Native Developer to join our growing engineering team and help lead our expansion into mobile. This is a role for someone who cares deeply about product quality, enjoys solving architectural challenges, and wants ownership over real features that users rely on.

You’ll play a key role in building and scaling our mobile applications, shaping the future of our mobile offering, and collaborating closely with backend and product teams to deliver a seamless, reliable, and high-performance user experience.

• Lead the development and delivery of new mobile product features.
• Maintain and improve the existing React Native codebase, performance, and stability.
• Define and evolve mobile architecture, system design, and technical strategy.
• Partner with backend, product, and design teams to shape solutions that scale.
• Drive reliability, performance, and observability standards on mobile.
• Own production debugging, incident investigation, and root cause analysis.
• Guide improvements in build systems, CI/CD, releases, testing, and app store deployments.
• Mentor engineers and foster a culture of quality, ownership, and execution.
• Support hiring and help grow a world-class mobile engineering team.
• Champion performance across rendering, navigation, latency, memory, offline behavior, caching, and real-time experiences.
• Lead with accountability for failure cases, API degradation, recovery UX, and resilience.

• 5+ years of experience building mobile applications, with significant React Native experience.
• 2+ years in a technical leadership, lead, or architect role.
• Experience mentoring engineers through code reviews, architecture, and incident response.
• Strong understanding of mobile system design, component architecture, state management, navigation patterns, and performance trade-offs.
• Experience optimizing UI performance, memory usage, rendering efficiency, and startup time.
• Deep knowledge of React internals and rendering behavior (hooks, reconciliation, lifecycle, render cost).
• Experience working with native modules and iOS/Android bridging.
• Shipped and maintained apps on the App Store and Google Play.
• Experience with CI/CD, builds, release automation, and OTA updates (EAS, Code Push, or similar).
• Experience implementing monitoring and observability (Sentry, Open Telemetry, crash reporting, performance tracing).
• Demonstrated ownership of edge cases, distributed failure modes, degraded APIs, offline sync, and recovery UX.
• Demonstrated ability to lead architecture or technical strategy for a mobile app or major feature.
• Maintains high standards for clean code, SOLID principles, maintainability, and documentation.
• Proven experience leading and mentoring mobile engineers.
• Proven ownership of technical strategy or architecture for mobile apps or features.
• Proven ability to coach others and raise the bar across a team.
• Leads cross-team alignment during ambiguity or incidents.

• Experience in startup or high-ownership product teams.
• Experience scaling real-time or multi-region mobile architectures.
• Experience designing or building design systems, shared component libraries, or mobile platform foundations.
• Experience improving mobile security, analytics, performance profiling, and release automation.
• Knowledge of edge caching, streaming real-time events, Web Sockets, or offline-first architectures.

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.

Discover the perks of being part of our vibrant team! We offer:

• Remote Work Environment: Embrace the freedom to work…