Sébastien Castiel
Staff Software Developer at Vasco
Montreal, Quebec, Canada
Summary
🤩
Rockstar🎓
Top SchoolSébastien Castiel is a Senior Software Developer based in Montreal with 11 years of experience building and leading frontend and full-stack teams across finance, fintech, and consumer products. He combines hands-on engineering (React, Next.js, Rails, Java) with coaching—running workshops, mentoring developers, and authoring five books on frontend development. His background includes leading client-data and real-time trading features at Wealthsimple and Adaptive Financial Consulting, and contributing to a modular web/mobile framework at National Bank of Canada. Now at Vasco, he continues to bridge product and engineering while offering practical training that helps developers ship their first React & Next.js apps. Outside work he channels curiosity into continuous learning and long hikes across Quebec, a habit that informs his patient, persistent approach to mentorship and problem solving.
11 years of coding experience
14 years of employment as a software developer
Engineer’s Degree Computer Science, Engineer’s Degree Computer Science at INSA Rennes
English, French
Stackoverflow
166reputation
8kreached
9answers
1question
Github Skills (177)
authentication10
shadcn-ui10
javascript10
react-components10
jwt10
tailwindcss10
documentation10
vercel10
reason-react10
open-source10
nextjs10
export-to-html10
oauth10
react10
rich-text-editor10
Programming languages (16)
Github contributions (5)
scastiel/protonmail-export
Nov 2016 - Jul 2018
Export your ProtonMail e-mails. DEPRECATED, prefer ProtonMail Bridge: https://protonmail.com/bridge
Contributions:7 commits, 3 PRs, 5 pushes in 1 year 8 months
e-mail
scastiel/taxntip
Mar 2018 - Jul 2018
🇨🇦📱💵 Taxes and tips in Canada
Contributions:47 commits, 4 PRs, 15 pushes in 4 months
taxes
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