Leonardo Massaroli, Developer in Buenos Aires, Argentina
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Leonardo Massaroli

Verified Expert  in Engineering

Bio

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

LastRev
CSS, React, TypeScript, Next.js, Pixel Perfect, JavaScript, Contentful, GraphQL...
AccessPay
Angular, TypeScript, Jira, Slack, Git, Azure, ECMAScript (ES6), Windows...
Intive
React, TypeScript, Redux, Redux-Saga, CSS, HTML5, Sass, Git, HTML, REST APIs...

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

Part-time

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

2023 - 2023
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.
Technologies: CSS, React, TypeScript, Next.js, Pixel Perfect, JavaScript, Contentful, GraphQL, REST

Senior Front-end Developer

2022 - 2022
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.
Technologies: Angular, TypeScript, Jira, Slack, Git, Azure, ECMAScript (ES6), Windows, Web Applications, Web Development, Front-end Development, Startups, Single-page Applications (SPAs)

Senior Front-end Developer

2021 - 2022
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.
Technologies: React, TypeScript, Redux, Redux-Saga, CSS, HTML5, Sass, Git, HTML, REST APIs, APIs, JavaScript, DevOps, CI/CD Pipelines, Amazon Web Services (AWS), Slack, Jest, Front-end, GitHub, Visual Studio Code (VS Code), ECMAScript (ES6), Windows, Jira, Unit Testing, Web Applications, Web Development, Front-end Development, Enterprise, Single-page Applications (SPAs), REST

Semi-senior Front-end Developer

2020 - 2021
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.
Technologies: JavaScript, React, Next.js, Styled-components, CSS, HTML5, Git, HTML, Postman, Figma, REST APIs, APIs, DevOps, CI/CD Pipelines, Slack, Jest, Front-end, Visual Studio Code (VS Code), ECMAScript (ES6), Material UI, Windows, Jira, Unit Testing, Web Applications, Web Development, Front-end Development, Startups, Single-page Applications (SPAs), REST

Full-stack Engineer

2017 - 2021
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.
Technologies: Node.js, React, TypeScript, JavaScript, Babylon.js, MySQL, Test-driven Development (TDD), Socket.IO, CSS, HTML5, Git, HTML, Full-stack, Full-stack Development, Express.js, REST APIs, APIs, WebSockets, Sockets, Slack, Front-end, Back-end, GitHub, Visual Studio Code (VS Code), Chart.js, ECMAScript (ES6), 2D Games, Games, Unit Testing, SQL, Google Cloud, Electron, Web Applications, Babel, Web Development, Front-end Development, Back-end Development, OAuth, WebGL, Desktop App Development, Startups, Single-page Applications (SPAs), REST

Software Engineer

2016 - 2019
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.
Technologies: Front-end, Back-end, React, Heroku, Node.js, MySQL, Mocha, JavaScript, CSS, HTML5, Git, HTML, Postman, MongoDB, REST APIs, APIs, TypeScript, Express.js, DevOps, CI/CD Pipelines, Slack, GitHub, ECMAScript (ES6), Jira, Web Applications, GraphQL, Web Development, Front-end Development, Back-end Development, Android, Startups, Mobile App Development, React Native, REST

Experience

Fighting Video Game

I worked as a full-stack developer on a video game project that involved multiple NPCs fighting each other.

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

I was part of a three developers team for developing an online turn-based videogame. My role there was as a senior full-stack developer using technologies like Node.js, React, and Babylon.js.

The whole game was created from scratch and reached over 1,000 users.

Pixi Shooter

https://github.com/leoflood/pixi-shooter
This is a 2D demo shooter video game where the player will try to survive the enemy waves that will appear.

I 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/ezejedrez
Developed a chess game from scratch with React Native and TypeScript. The movement of all the pieces was designed using test-driven development to ensure that all the game rules are tested, and there are no errors.

Education

2011 - 2017

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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