James Hemery
Co-founder & CTO at CroissancePlus
Paris, Ile-de-France
Summary
👤
SeniorJames Hemery is a Paris-based serial tech entrepreneur and Co-founder & CTO of Yield Studio, where he grew an auto-financed digital product agency from zero to €2.5M ARR with ~20 people by combining Lean product practices and measurable ROI. With nine years of experience that began in freelance work at 16, he blends hands-on engineering—contributing to open-source backend tooling like express-fileupload—with strategic product, data and AI advisory for SMEs and enterprises. He regularly speaks on tech, product and business topics, co-hosts a tech podcast, and invests in early-stage ventures, reflecting a genuine appetite for community building and scalable impact. Notably, his approach emphasizes shipping quality code fast (many products launched under three months) while aligning engineering decisions tightly to business outcomes.
9 years of coding experience
7 years of employment as a software developer
French, English
Github Skills (7)
nodejs10
javascript10
middleware10
expressjs10
file-upload10
testing9
unit-testing9
Programming languages (7)
Github contributions (5)
richardgirges/express-fileupload
Dec 2018 - Dec 2018
Simple express file upload middleware that wraps around busboy
Role in this project:
Back-end Developer
Back-end DeveloperContributions:9 commits, 1 PR, 2 comments in 2 days
Contributions summary:James focused on enhancing the functionality of the `express-fileupload` middleware. Their work involved implementing features like parsing nested objects within request bodies and incorporating a `parseNested` option for flexible data handling. They added unit tests to validate the parsing of nested data and ensure the correct behavior of the `parseNested` option, demonstrating a strong understanding of the library's core logic. Furthermore, the user contributed to code quality by fixing ESLint rules and refactoring existing code.
fileuploadfile-uploadexpressjsupload-filewraps
YieldStudio/laravel-expo-notifier
Nov 2022 - Dec 2022
Easily manage Expo notifications with Laravel. Support batched notifications.
Contributions:7 releases, 2 reviews, 30 commits in 1 month
expo-notificationsbatchpush-notificationsnotificationsnotifier
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