Fumiya Kume
Android Developer at Mercari, Inc.
Tokyo, Japan
Summary
👤
Senior🎓
Top SchoolFumiya Kume is an Android developer with over 10 years in software engineering and 5+ years building Mercari’s Android app used by millions. He combines deep Kotlin and modern architecture expertise with a passion for AI-assisted development, having led Cursor deployment to 2000+ engineers and evangelized Vibe Coding internally. An active open-source contributor (180+ repos) and maintainer of a Protobuf-to-Android client generator, he has shipped conference and community apps like DroidKaigi and contributed to cross-platform projects such as PoGo-UWP. A seasoned community organizer and speaker—hosting meetups that reached thousands and speaking at Developers Summit and KotlinFest—he blends technical craft with developer advocacy. Based in Tokyo, he enjoys tackling foundational platform work (e.g., M1 Mac support for Android dev) and curates notable AI adoption resources for Japanese companies.
10 years of coding experience
Computer science, Information Technology, Computer science, Information Technology at Daido University
Github Skills (9)
kotlin10
android-ui10
mobile-development10
csharp10
android10
dotnet-core10
localization9
xaml8
git7
Programming languages (19)
Github contributions (5)
DroidKaigi/conference-app-2019
Jan 2019 - Jan 2019
The Official Conference App for DroidKaigi 2019 Tokyo
Role in this project:
Mobile Developer (Android)
Mobile Developer (Android)Contributions:19 commits, 2 PRs, 12 comments in 22 days
Contributions summary:Fumiya primarily contributed to the Android application for the DroidKaigi 2019 conference. Their work included removing null checks, merging updates from the master branch, and adding the Contributor Screen. Furthermore, the user modified files related to survey functionality, suggesting involvement in the app's interactive features. The changes point towards feature implementation, UI adjustments, and database interaction within the context of an Android application.
androiddroidkaigikotliniosflutter
ST-Apps/PoGo-UWP
Jul 2016 - Aug 2016
UWP Client for Pokemon Go
Role in this project:Full-stack Developer
Full-stack DeveloperContributions:6 commits, 3 PRs, 8 comments in 6 days
Contributions summary:Fumiya contributed to the project by modifying both the front-end and back-end aspects. They made changes to UI elements, including adding and removing assets, and updating the application's splash screen. They also incorporated internationalization by adding language files, demonstrating a focus on application localization. Additionally, the user made code improvements, using null propagation and merging branches.
dotnetuwpwindowscsharppokemon-go
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.