Geoffrey Testelin
Développeur Front-end at Decathlon
Lille, Hauts-de-France
Summary
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Rockstar🎓
Top SchoolGeoffrey Testelin is a pragmatic front-end developer with 11 years of experience building Angular and TypeScript applications for both B2B and B2C products, currently working at Decathlon in Lille. He specializes in Reactive patterns (RxJS), component libraries, and frontend tooling—leading migrations (Jasmine→Jest, TSLint→ESLint) and creating shareable web-component libraries across multiple employers. An active OSS contributor, he’s improved the popular actions/stale GitHub Action by enhancing label handling, test coverage and logging, showing attention to stability and QA. Comfortable in English and French teams, he pairs clean-code discipline with practical testing (Jest, Cypress) and a designer’s eye for SCSS/Pug stacks. Colleagues know him for balancing engineering rigor with developer ergonomics—his “recipe” hints at a taste for well-crafted, maintainable front-end systems.
11 years of coding experience
7 years of employment as a software developer
Baccalauréat with Honors, STI 2D - IT and technologie information (SIN), Baccalauréat with Honors, STI 2D - IT and technologie information (SIN) at Industrial and Commercial High School (LICP)Master of Science (M.Sc.), IT, Master of Science (M.Sc.), IT at SUPINFO - The International Institute of Information Technology
German, English, French
Stackoverflow
924reputation
267kreached
29answers
29questions
Github Skills (20)
unit-testing10
javascript10
jes10
testing10
typescript10
jestjs10
typescript-types10
jtest10
typescripts10
unit-test10
github-ci9
githubaction-workflow9
yeoman6
html6
css-position6
Programming languages (12)
Github contributions (5)
actions/stale
Nov 2020 - Oct 2021
Marks issues and pull requests that have not had recent interaction
Role in this project:
Back-end Developer & QA Engineer / Test Automation Engineer
Back-end Developer & QA Engineer / Test Automation EngineerContributions:151 reviews, 48 commits, 48 PRs in 10 months
Contributions summary:Geoffrey primarily contributed to the `actions/stale` repository by implementing and testing features related to labels and their interaction within the issue processing workflow. They fixed issues concerning label syntax and the removal of labels, alongside adding new options. The user also wrote tests to validate the functionality and address various scenarios, and enhanced logging for better debugging. The contributions show a focus on maintaining the core logic and ensuring the stability of the action.
markspull-requestsinteraction
Sonia-corporation/ngx-achievements
Jul 2021 - Jul 2025
Check and manage the achievements of your IT team.
Contributions:61 reviews, 72 PRs, 106 pushes in 4 years
monoreporeactjavascriptexpressteam-it
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