Ryo Matsukawa
ソフトウェアエンジニア at Mercari, Inc.
Tokyo, Japan
Summary
🤩
Rockstar🎓
Top SchoolRyo Matsukawa is a front-end software engineer based in Tokyo with five years of experience building accessible, performant React UI components. He has contributed to high-profile open-source projects like React Spectrum and Stylelint, fixing accessibility bugs and improving linting rules that help many developers avoid CSS pitfalls. As a member of pnpm and Stylelint and an ex-contributor to HeroUI/NextUI, he blends practical library maintenance with product-focused UI work. Ryo’s work emphasizes accessibility and developer experience—adding aria support, directory handling for file components, and robust tests. Currently at Mercari, his background includes fast-paced startup and enterprise roles, plus a non-traditional CS foundation from 42 Tokyo. Colleagues value him for shipping deliberate UI fixes that quietly improve usability across an ecosystem.
5 years of coding experience
1 year of employment as a software developer
Completed Common Core, Completed Common Core at 42 Tokyo
Github Skills (19)
accessibility10
javascript10
ui-components10
css10
typescript10
component-kit10
component-library10
typescript-types10
linter10
typescripts10
react10
testing9
react-components9
react-component9
postcss9
Programming languages (11)
Github contributions (5)
heroui-inc/heroui
Apr 2023 - Feb 2025
🚀 Beautiful, fast and modern React UI library. (Previously NextUI)
Role in this project:
Front-end Developer
Front-end DeveloperContributions:124 reviews, 53 PRs, 100 pushes in 1 year 10 months
Contributions summary:Ryo primarily contributed to the development and improvement of the React UI library, focusing on accessibility and functionality of UI components. Their work included enhancing tab accessibility, updating documentation for modal features, and fixing UI-related issues such as accordion divider display and modal form input behavior. They also addressed issues with links in documentation and implemented UI improvements.
reactui-libraryreact-componentsreactjscomponent-library
stylelint/stylelint
Oct 2024 - Mar 2025
A mighty CSS linter that helps you avoid errors and enforce conventions.
Role in this project:Full-stack Developer
Full-stack DeveloperContributions:173 reviews, 77 PRs, 84 pushes in 5 months
Contributions summary:Ryo primarily contributed to the `stylelint/stylelint` repository by fixing bugs and improving the accuracy of various linting rules. Their work included refining existing rules like `declaration-block-no-redundant-longhand-properties`, `length-zero-no-unit`, `selector-attribute-name-disallowed-list`, and several others. They also addressed reported ranges and added new test cases, ultimately enhancing the quality and robustness of the stylelint project.
linterlintenforce-conventionssugarsspostcss
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