Leonardo De Castro
São Paulo, Brazil
Summary
👤
Senior🎓
Top SchoolLeonardo De Castro is a senior JavaScript developer from São Paulo with over a decade of experience building scalable, high-performance web applications and microfrontend architectures. He has a strong track record delivering production systems for enterprises like Pinterest and Blue Yonder, including migrations (npm→pnpm), sandboxed micro-frontends, and robust E2E testing that reduced flakiness across CI/CD. Comfortable across the full stack, he regularly crafts responsive component libraries, integrates CMS-driven workflows, and architects Node.js microservices to replace legacy monoliths. His work spans startups and large organizations—from launching an AI-powered SEO platform to shipping medical imaging tools—demonstrating both product-oriented thinking and technical rigor. Notably, he blends hands-on implementation with experiment-driven product improvements (conversion modules and advertiser experiments) to drive measurable adoption. Fluent in modern JS tooling (TypeScript, Next.js, React, Turborepo, pnpm) and cloud-native delivery, he pairs pragmatic engineering with a keen eye for UX and maintainability.
10 years of coding experience
7 years of employment as a software developer
Computer Technician, Software development, Computer Technician, Software development at Colégio Técnico ETEP
Portuguese, English, Spanish
Stackoverflow
11reputation
3kreached
1answer
2questions
Github Skills (31)
javascript9
css9
html9
frontend8
compiler8
commonjs8
textarea8
testing8
react-native7
zero-configuration7
ios7
android7
react7
nginx6
cornerstone6
Programming languages (3)
Github contributions (5)
leonardosarmentocastro/cna
Aug 2022 - Jun 2024
Contributions:109 pushes, 1 branch, 49 tags in 1 year 11 months
leonardosarmentocastro/create-nodejs-app
May 2019 - May 2021
Contributions:247 commits, 14 PRs, 130 pushes in 2 years
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