Kieran Crown

Lead mobile engineer at Onsera Health, owning the React Native and Expo app and setting the technical direction for the mobile platform.

• Lead the mobile engineering effort, owning architecture, releases, and technical direction for the Expo app
• Set standards for code quality, testing, and CI/CD across the mobile codebase
• Partner closely with product and design to ship polished, reliable health experiences
• Mentor engineers and champion best practices across the mobile stack

Senior full stack engineer in a team of fewer than four, owning both the Expo-based mobile app and the GraphQL orchestration layer integrating with legacy telecom APIs.

• Own the full Expo mobile app and GraphQL orchestration layer for a telecom product
• Span feature development, bug fixes, app releases, CI/CD maintenance, and test coverage
• Serve as primary owner of the mobile codebase, collaborating closely with backend engineers
• Balance frontend polish with backend integration in a fast-paced, small team environment

Sole mobile engineer at a digital banking app focused on savings and financial inclusion, driving a significant modernisation effort across the React Native codebase.

• Owned the full React Native codebase as the sole mobile engineer
• Migrated the app to the latest Expo SDK and React Native's new architecture
• Implemented a design system using Shopify Restyle and Reanimated
• Built CI/CD pipeline in GitHub Actions with integrated Maestro end-to-end tests
• Reworked state management for improved reliability across financial features

Worked on Official, a relationship wellness app acquired by Bumble, leading a codebase rewrite and expanding test coverage.

• Led a full rewrite of a codebase originally built by contractors, improving quality and maintainability
• Expanded Maestro end-to-end test coverage, improving release confidence and reducing production issues
• Contributed to sprint planning and worked closely with product to shape the roadmap
• Consistently brought ideas to improve UX and overall app quality

Built mobile features for the cashback and payments team, including leading Apple Pay and Google Pay integration.

• Led the implementation of Apple Pay and Google Pay, coordinating directly with both companies through certification
• Built contactless payment acquisition, swipe-based transaction history, and cashback card management features
• Owned the redesign of the retailer's view and improved transaction list performance
• Collaborated with design and two engineering teams to build a shared UI component library adopted across multiple apps

Contributed to the React Native integration layer connecting with existing iOS, Android, and web platforms at a digital media protection company.

• Contributed to the React Native integration layer connecting with existing native platforms
• Gained experience in cross-platform development and integrating modern mobile frameworks with established native systems

Consolidated backend infrastructure and led frontend modernisation at a leading UK WebPrint provider.

• Migrated from multiple Node.js servers to a unified AWS deployment using Terraform
• Led frontend modernisation from a legacy Java stack to Next.js
• Improved performance, maintainability, and developer experience across the platform

Worked on mobile cloud engineering initiatives at a major defence and aerospace company, gaining exposure to enterprise-scale cloud infrastructure.

• Worked on mobile cloud engineering initiatives within a highly regulated environment
• Gained exposure to enterprise-scale cloud infrastructure and security-focused development practices
• Obtained AWS Certified Developer certification

Built interactive digital experiences for brands and event organisers at a creative technology agency.

• Built a company-wide mobile app using React, Cordova, and Node.js
• Developed an iPad wall installation for clients including TikTok, a system where hundreds of iPads sync to display a single video
• Each device supported independent interaction and seamless spatial repositioning using QR-based recognition