Harrison Mendonça, Developer in Rio de Janeiro - State of Rio de Janeiro, Brazil
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Harrison Mendonça

Verified Expert  in Engineering

Software Developer

Rio de Janeiro - State of Rio de Janeiro, Brazil
Toptal Member Since
June 24, 2019

Harrison is a front-end developer with 13 years of experience developing apps, websites, and interactive installations. He founded Grama, a front-end services company, and Cammada, an online marketplace for 3D printing. Harrison studied Graphic Design in Brazil and devotes his extra time to research and experimentation.


React Native, Redux, Firebase, TypeScript, Bitrise, Objective-C, Java
Mude Wellness Media
Amazon Web Services (AWS), REST APIs, Redux, Prototyping, Firebase, Slack...
Amazon Web Services (AWS), REST APIs, Redux, Prototyping, Firebase, Slack, CSS...




Preferred Environment

Figma, Slack, GitHub, Visual Studio Code (VS Code), MacOS

The most amazing...

...project I've created was a web app for more than one million people to access on the same day and check their grades to get access to University.

Work Experience

Senior React Native Engineer

2021 - 2021
  • Developed the new Belk app in React Native, fusing in performance and maintainability.
  • Helped to integrate and build the app using Bitrise for CI/CD.
  • Connected the app with the Salesforce back end, native camera, push notifications, and geolocation.
Technologies: React Native, Redux, Firebase, TypeScript, Bitrise, Objective-C, Java

Front-end and React Native Developer

2018 - 2021
Mude Wellness Media
  • Developed, published, and maintained the React Native app.
  • Set up CI/CD with Bitrise service and Slack integration.
  • Developed the integration with services like Google Maps, Vimeo, and PagarMe, a payment gateway.
Technologies: Amazon Web Services (AWS), REST APIs, Redux, Prototyping, Firebase, Slack, Bitrise, CSS, WordPress, Scrum, Git, SCSS, Node.js, React Native, React, JavaScript, Cordova

Founder | CTO

2015 - 2019
  • Led a team of five front-end developers. Hired and managed developers and a project owner.
  • Resolved complex development tasks that the team couldn't do.
  • Organized briefings and scrum calendar and finances.
Technologies: Amazon Web Services (AWS), REST APIs, Redux, Prototyping, Firebase, Slack, CSS, Next.js, Three.js, Scrum, Git, PHP, MySQL, MongoDB, Express.js, SCSS, Node.js, React Native, JavaScript, WordPress, WebKit, React

Senior Developer

2015 - 2018
  • Developed the main company platform to search and watch video lessons using React.
  • Served as the front-end lead of a tool that students could consult their national score of exams. On the launch day, it achieves one million users. Used AWS S3 to cache the dynamic data.
  • Created the thread feature (like Slack) for live chat during the online lessons.
  • Added visual animations and a responsive layout for landings.
  • Removed malware and saved the blog source code from a shared hosting service.
Technologies: Amazon Web Services (AWS), REST APIs, TypeScript, Flow, Redux, Prototyping, Slack, CSS, Next.js, WordPress, Scrum, WebKit, Git, MongoDB, Express.js, Node.js, JavaScript, SCSS, GraphQL, Jest, React

Co-founder and CTO

2015 - 2017
  • Developed a marketplace for 3D printing.
  • Improved shipping service with dedicated Lambda function in AWS.
  • Organized and implemented a design system for UI/UX.
  • Create a client-side calculation for volumes of a 3D file (.stl).
  • Developed an online calculator with form and graphics for printer shops to estimate their cost and price.
Technologies: REST APIs, Prototyping, Slack, CSS, Scrum, Git, PHP, MySQL, SCSS, Node.js, JavaScript, Amazon Web Services (AWS), WordPress, Laravel, React

Senior Developer

2012 - 2014
  • Developed interactive installations with a high level of interactive and visual effects.
  • Processed different user inputs like Kinect, electronic sensors, sound spectrogram, etc.
  • Managed the software for big companies, like Tesla, Solar City, and SXSW.
  • Contributed to video mapping with custom software developed in house.
  • Manage a junior developer and a designer to develop good solutions in a short timeframe.
Technologies: REST APIs, Prototyping, WordPress, Git, PHP, MySQL, SCSS, Node.js, React, JavaScript, Flash ActionScript, Arduino, Processing, C++, OpenFrameworks

Mude - Wellness App

As a unique front-end developer, I programmed the whole app with React Native with the support of just one back-end developer. It's full of features like scheduling classes, live classes, notifications, chat, payments, maps, geolocation, timezones, QR code, offline-first, and more.

Descomplica - Educational Platform

This is the biggest education platform in Brazil for University entrance exams. It has more than a million access during the previous day of exams. Here I developed a lot with React; when React was still 0.14, good times. We also used GraphQL and developed the site from the sketch. I also did some small projects with different technologies to complete the whole environment.

JOCO - Webapp for Learning

I ported the legacy version (Angular 1.5) to React, adding many animations and transitions and turning it into a SPA for a better experience. I also created a config JSON model to customize and embrace different brands allowing the product to scale.

Cammada - 3D Printing Marketplace

In this project I was a co-founder then developed everything, front end, back end, and infrastructure. I also did a lot of design because we hired a designer for the base styles.

There was one unique challenge, the shipping feature. It was plugged into two different systems with almost 30 requests for a specific price. So I solved it with a Lambda function in AWS that runs in parallel. Then 50 seconds of requests became two seconds.
2005 - 2011

Bachelor's Degree in Graphic Design

Federal University of Rio de Janeiro - UFRJ - Rio de Janeiro, Brazil


REST APIs, Node.js, React, Three.js


GitHub, Adobe Illustrator, Slack, Trello, Git, Figma, Flow, Sketch


Next.js, Redux, React Native, Jest, OpenFrameworks, Laravel, Express.js, Express.io


Flash ActionScript, CSS, JavaScript, SCSS, GraphQL, C++, Processing, TypeScript, PHP, Objective-C, Java




WordPress, Visual Studio Code (VS Code), Arduino, Bitrise, Firebase, Amazon Web Services (AWS)


MySQL, MongoDB


Prototyping, WebKit, Cordova

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