
Leonardo Massaroli
Verified Expert in Engineering
Front-end Developer
Buenos Aires, Argentina
Toptal member since October 11, 2022
Leonardo is an IT professional with a solid background in the design of web applications. Having experience working both freelance and as part of teams of diverse companies, both enterprise and startups, he specializes in React, TypeScript, and Node.js. Leonardo is eager to apply his knowledge to benefit new clients and contribute to exciting projects that impact the world.
Portfolio
Experience
- JavaScript - 6 years
- Web Development - 6 years
- Full-stack - 3 years
- React - 3 years
- TypeScript - 3 years
- Node.js - 3 years
- Express.js - 2 years
- Next.js - 1 year
Availability
Preferred Environment
Slack, GitHub, TypeScript, React, Node.js, JavaScript, Amazon Web Services (AWS)
The most amazing...
...project I've created from scratch is a strategic online video game with more than 1,000 users.
Work Experience
Front-end Developer
LastRev
- Utilized Contentful as a CMS and implemented GraphQL for efficient data retrieval from the CMS to the front end, enhancing website performance and reducing content delivery time.
- Developed and implemented new features and components, concurrently managing multiple client environments and improving project efficiency.
- Resolved bugs, ensuring seamless user experiences and reducing customer requests.
Senior Front-end Developer
AccessPay
- Developed and maintained the front end of new administrative pages from scratch using TypeScript.
- Provided support to my teammates and did pair programming with them in those parts that were needed.
- Tracked and fixed bugs using Jira as a reporting tool.
Senior Front-end Developer
Intive
- Started a new team from scratch for a customer dedicated to maintaining and improving a free ad-supported streaming platform.
- Made the existing app work on a new branch of devices. Solved bugs and created unit tests to ensure all devices functioned correctly.
- Improved the app accessibility by migrating the JavaScript text to speech (TTS) used before for Accessible Rich Internet Applications (ARIA) labels.
Semi-senior Front-end Developer
Globant
- Listed the information of the company's customers and modified it by creating a back office app for a customer dedicated to an agriculture eCommerce.
- Designed the back office app from scratch using Confluence, Jira, and Figma and developed it in React using the Next.js framework.
- Collaborated with the team and back-end developer to sync the front end with the back end through an application programming interface (API).
- Promoted to semi-senior advance role thanks to my good performance in the project and satisfying the client's needs.
Full-stack Engineer
Independencia Juego
- Reached more than 1,000 users on a multiplayer 3D strategy game about the independence of South America.
- Created the game from scratch by developing its front end, back end, and database using React, Node.js, and MySQL technologies.
- Migrated the app to React, which initially used HTML, CSS, and Vanilla JS.
- Applied test-driven development (TDD) for the game rules, such as combat between units, using Mocha for testing.
- Hosted the entire game on the Google Cloud Platform and then on Heroku.
Software Engineer
Freelance
- Developed projects for clients and myself using technologies and good practices such as TDD, front-end and back-end development, React, React Native, TypeScript, Heroku, Node.js, MySQL, Mocha, Jest, and functional programming.
- Automated the parsing of my client's leads by developing email parsers and the back end.
- Improved the leads saving process of a client by creating a web application where the lead info is placed and then converted into JSON, capable of being saved to the MongoDB database.
Experience
Fighting Video Game
My responsibilities included improving and fixing existing functionality, creating new features, and migrating the project from a down CMS to a new host with a new database.
ACCOMPLISHMENTS
• Used Google Cloud and MongoDB for the migration.
• Created unit tests for the complex parts of the code.
• Fixed the players' collision system.
• Created and applied a random map generator algorithm for the game using tiles.
• Changed the players' sprite sheet from two directions to four directions.
• Added in-game chests and power-ups.
• Refactored the screens and applied React in the interfaces.
• Added the possibility to focus on a specific player in-game.
• Deployed the game in Google Cloud and applied continuous deployment to speed up the deployment process.
Online Video Game
The whole game was created from scratch and reached over 1,000 users.
Pixi Shooter
https://github.com/leoflood/pixi-shooterI created the game from scratch and developed it with React, TypeScript, and the PixiJS framework. I also designed the code structure of the entities in the game by using the composite design pattern. Finally, I applied test-driven development (TDD) for the complex parts of the code using Jest.
Ezejedrez
https://github.com/sophie-games/ezejedrezEducation
Technician in Graphic Design
Escuela Técnica N°6 Fernando Fader - Buenos Aires, Argentina
Skills
Libraries/APIs
React, Node.js, Socket.IO, REST APIs, Sockets, Babylon.js, Redux-Saga, Chart.js, WebGL
Tools
Git, Slack, Figma, Webpack, GitHub, Expo, Mocha, Postman, Jira, Babel, ChatGPT
Languages
TypeScript, JavaScript, CSS, HTML, HTML5, ECMAScript (ES6), SQL, Sass, GraphQL
Frameworks
PixiJS, Jest, Next.js, Redux, Express.js, React Native, Material UI, Electron, Angular, Tailwind CSS, Ionic
Paradigms
Unit Testing, REST, DevOps, Test-driven Development (TDD), Desktop App Development
Storage
MySQL, MongoDB, Google Cloud, PostgreSQL, NoSQL
Platforms
Heroku, Windows, Visual Studio Code (VS Code), Amazon Web Services (AWS), Azure, Docker, Google App Engine, Android, Contentful
Other
Vite, Front-end, Back-end, Full-stack, Full-stack Development, WebSockets, Games, 2D Games, Web Applications, Web Development, Front-end Development, Back-end Development, Single-page Applications (SPAs), APIs, Composite, Styled-components, ESLint, CI/CD Pipelines, Design, OAuth, OpenAI GPT-3 API, Startups, Enterprise, Mobile App Development, Pixel Perfect
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