Guillaume Demesy
CEO, Software Engineer at Splitfire
France
Summary
🤩
Rockstar🎓
Top SchoolGuillaume Demesy is a French software engineer and founder with 13 years of hands-on experience building web applications and running Splitfire as CEO since 2012. He combines full-stack development skills with entrepreneurial leadership, shipping pragmatic solutions for clients while continuing to contribute to open-source tooling. Notably, he enhanced Rome’s developer toolchain by implementing granular CSS vendor-prefix support for properties like border-radius and backdrop-filter, demonstrating attention to cross-browser UX details. Trained in mathematics and computer science, he brings a methodical, test-driven approach to front-end challenges and a personal commitment to balancing craft with family life.
13 years of coding experience
1 year of employment as a software developer
Licence, Mathematics and Computer Science, Licence, Mathematics and Computer Science at Université Henri Poincaré, Nancy 1IUT CharlemagneDéveloppeur Logiciel, Développement Logiciel, Développeur Logiciel, Développement Logiciel at Centre Afpa Pompey
English, French
Stackoverflow
1reputation
0reached
0answers
0questions
Github Skills (11)
linter10
css10
javascript10
webpages10
web-content10
typescript-types9
toolchain9
animation9
typescript9
typescripts9
react3
Programming languages (14)
Github contributions (5)
rome/tools
Apr 2021 - Apr 2021
Unified developer tools for JavaScript, TypeScript, and the web
Role in this project:
Front-end Developer
Front-end DeveloperContributions:6 reviews, 6 commits, 6 PRs in 5 days
Contributions summary:Guillaume focused on enhancing the Rome tools by adding CSS prefix support. Their contributions include implementing features for `position`, `box-sizing`, `border-radius`, `animation`, `backdrop-filter`, and `user-select`. The code changes involved modifications to the `index.ts` file, as well as creating and updating files for individual CSS properties within the `prefixes` directory to handle vendor prefixes. Test fixtures within the `test-fixtures` directory were also updated to reflect the changes.
javascripttypescriptformatterlintertoolchain
webcompat/webcompat-editor-testing
Aug 2020 - May 2022
Webcompat dashboard editor testing
Contributions:24 reviews, 39 PRs, 75 pushes in 1 year 8 months
testing
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