KiraKiran
Customer and appointment management for independent nail salons.
iOS · React Native · ExpoReact Native engineer focused on practical, high-quality mobile apps.
Six years of end-to-end ownership from architecture to store release.
Based in Nara, working with teams in Osaka and worldwide.

Featured project
Employee recognition and rewards used by organizations with frontline teams.

Small products built around problems I know personally, then shipped and maintained.
Reliable staging coverage for real iOS and Android flows.
Built a staging-locked Maestro and YAML black-box harness covering smoke, adversarial, CRUD, restart, public-booking, and Stripe card PaymentSheet flows. Added stable selectors, safety guards, JUnit reports, screenshots, cleanup, and device targeting. Cross-role messaging was designed and instrumented as a coordinated two-device protocol.
From Guusto engineering leadership
“He demonstrated strong technical independence, handling feature development, releases, production issues, and the day-to-day challenges of maintaining a mobile application in production.”
I joined Guusto when the company had seven employees. Before a product team was hired, I often decided what needed attention next. Later I worked from Figma designs and Jira tickets with product, design, backend, and web teams.






Each product began with a problem I wanted to solve.
Customer and appointment management for independent nail salons.
Japanese-first React Native and Expo app with calendars, client history, reference photos, Supabase row-level security, and a staging-locked Maestro QA harness.
A shared movie queue that helps friend groups decide what to watch.
One Expo codebase for iOS and web, with Japanese and English localization, team scoring, TMDB and iTunes search, and Supabase persistence.
A quick, fair way for groups to choose an order, teams, or a winner.
React Native, Expo, TypeScript, and Reanimated. Supports 2 to 32 players, balanced teams, elimination rounds, undo, and reduced motion.
Mobile product work is the centre of my experience, supported by earlier web and game development.
Frontend Engineer, contract and remote
Sole React Native developer for the production iOS and Android app. Owned architecture, feature delivery, releases, incident response, performance work, reviews, and final technical handover.
Unity and C# developer
Built strategy, simulation, puzzle, RPG, and action prototypes for mobile, web, and desktop.
My strongest skills come from building, releasing, and supporting mobile apps.
“He played a foundational role in building the mobile app from the ground up, and his contributions have shaped the product in a lasting way.”
“He's not only a talented mobile engineer but also someone who's incredibly communicative, thoughtful, and easy to work with.”
I am looking for React Native and mobile product roles in Osaka, elsewhere in Japan, or remote.