About

I'm Koji Wakamiya, koji-1009 on GitHub. I build Flutter and Dart tools, and contribute to Flutter itself.

Contributions to Flutter

As of September 2026, 23 of my pull requests have been merged into flutter/flutter, 6 into flutter/packages and 3 into flutter/website. Several of them have been featured in Notable Commits, the lists of highlighted changes that the Flutter team publishes (2024, 2025, 2026).

Font fallback on iOS

Japanese text on iOS did not follow the requested font weight: font fallback in the Skia text stack always returned the weight-400 face of Hiragino Sans. I logged what the fallback returned for each requested weight and proposed a wrapper that picks the face of the requested weight, as a fix for #132475 in #179350. It was not merged.

Text input on the web

#180436 Fix IME and selection by syncing more text styles
#161593 Fix composing offsets when typing Japanese text
#166212 Fix the fallback font loading process

Keyboard and autofill on iOS

#182661 Fix keyboard flicker when switching text fields
#173598 Fix autofill context cleanup and view lifecycle management
#165637 Infer the autocorrect value from autofillHints

Images and memory

#184549 Add useLogicalPixels to ResizeImage
#180327 Add reportErrors to ImageStreamListener
#159945 Dispose the codec after frame creation, followed by the same fix across the framework, engine and tests

Widgets and packages

#180411 Add scrollCacheExtent to PageView
#152972 Remove the destination limit in NavigationRail
flutter/packages#9458 Support extension types in go_router_builder

Open source

shutter: renders a project’s widget previews to PNG and diffs two runs into before-and-after images
setup-flutter: sets up the Flutter SDK in GitHub Actions
paging_view: paged lists, in the spirit of Android Jetpack’s Paging 3
platform_image_converter: image format conversion using native APIs on iOS, macOS, Android and the web
dartrics: code-quality metrics and unused public API detection for Dart
flutter_auth_ui: Firebase Auth UI for Flutter (unofficial)

Elsewhere

GitHub · X (@D_R_1009) · Zenn (Japanese) · blog.dr1009.com (Japanese)