Juscyllan S.

About Me

Juscyllan is a Senior Full-stack Developer with 15+ years of development experience and a passion for innovation, technology, and optimum performance. He works with the latest JavaScript programming languages on client projects using JavaScript (ES Next), React Native, React.js, Express.js/Hapi.js, and MongoDB to deliver performant mobile applications for clients.

Frontend

Backend

Database

Other

Work history

UpStack
UpStack
Senior Full-stack Developer
2018 - Present (7 years)
Remote
  • Creating and developing innovative software solutions for clients across a broad range of industries.

  • Participating in scrums consisting of cross-functional teams, both software and hardware.

  • Ensuring that features are being delivered efficiently and on time.

Kujhy
Kujhy
Founder & CEO/CTO
2025 - Present
Maceió, Brazil

Relaunched the company with a focus on rapid, high-quality POC/MVP development and delivery for startups and enterprises.

React NativeReact Node.jsAWS CloudAI Programming TypescriptAWSTechnical Leadership Proof of Concept (POC) MVP
GigSmart
GigSmart
Senior React Native Developer
2019 - Present (6 years)
Remote
  • Led the critical migration from React Router to React Navigation, significantly improving performance and navigation patterns.

  • Developed responsive UI components for some of the platform's most used features, including Calendar, Roster, and Gig Series functionality.

  • Collaborating with back-end engineers to integrate GraphQL APIs while maintaining consistent UX across web, iOS, and Android platforms.

Kujhy
Kujhy
Founder/CTO
2015 - 2020 (5 years)
Maceió, Brazil
  • Designed, developed, and deployed web and mobile applications, working directly with stakeholders and startups.

  • Developed 20+ mobile applications using React Native and JavaScript, helping startups reach their customers through innovative web solutions.

  • Tracked, analyzed, and monitored technology performance metrics on client projects.

  • Pioneered React Native adoption since its early releases (2016), establishing cross-platform optimization techniques.

Zuq Performance
Zuq Performance
Full-stack Developer
2010 - 2015 (5 years)
Maceió, Brazil
  • Led the development and implementation of a complete, fully functional, offline-capable mobile application using Ionic and CouchDB in 1 month within the company.

  • Orchestrated the JavaScript culture modernization, transitioning from legacy jQuery/Backbone code to a more effective Angular.js.

  • Led the company's mobile and web development culture modernization.

  • Pioneered the adoption of PhoneGap and Ionic, allowing their entrance in the mobile apps market.

  • Engineered multiple bus arrival prediction algorithms using real-time GPS data, achieving +90% accuracy in urban environments.

Showcase

Full-stack Developer - Zauty.com
Full-stack Developer - Zauty.com
  • A platform connecting beauty professionals and clients.

  • The application is built using NodeJS, React, and a secured SPA.

  • The app utilizes React Native for mobile app development.

Full-stack Developer - GoKids
Full-stack Developer - GoKids
  • Develops a real-time application for monitoring children using GoKids' mother-drivers cars.

  • Built the application using JavaScript and React Native.

  • The application provides real-time information to users.

React Native Developer - Magote.com
React Native Developer - Magote.com
  • Developed and deployed an application for Magote.com, a beauty service marketplace in Brazil.

  • Integrated the app with the REST API provided.

  • Utilized OneSignal for push notifications.

React Native Developer - QuantoGastei
React Native Developer - QuantoGastei
  • App redesigned using React Native.

  • Improved app performance and usability.

  • App is now optimized for better user experience.

Education

BSc Computer Science
BSc Computer Science
Federal University of Alagoas, Computation Institute (UFAL) - Brazil
2007 - 2012 (5 years)