João Amadeu, Developer in Porto, Portugal
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João Amadeu

Bio

João is a versatile software engineer specializing in back-end services, APIs, and full-stack web and mobile development. With deep expertise in TypeScript, Go, Node.js, React, and React Native, he builds scalable, high-performance applications. Recently, João’s expanded into AI, creating intelligent agents with OpenAI and Cla. He's ready to bring smart, efficient solutions to future projects.

Portfolio

Bisect
React, TypeScript, Rust, Git, Azure, Teams, JavaScript, PHP, Cursor AI...
Kerico Home Clinic Services LLC
Node.js, React, JavaScript, React Native, Sentry...
Statement Mc
JavaScript, React, API Integration, Vercel, TypeScript, HTML, CSS, Chakra UI...

Experience

  • React - 6 years
  • Full-stack - 5 years
  • Git - 3 years
  • Amazon Web Services (AWS) - 3 years
  • OpenAI - 3 years
  • Node.js - 3 years
  • React Native - 3 years
  • Large Language Models (LLMs) - 2 years

Preferred Environment

MacBook, Linux, Discord

The most amazing...

...thing I developed is an IP Multi-viewer canvas designer tool that lets you move, add, and manage widgets (Viewports, PIP's, Audio meters).

Work Experience

Software engineer

2023 - 2026
Bisect
  • Built a canvas tool to let users arrange and manage a Multi-viewer stage by dragging and dropping nodes, scaling, rotating, and aligning them.
  • Created a real-time flowchart to let users visualize how decoders and encoders are connected in the network.
  • Refactored and migrated an old Angular app with Next.js and TypeScript.
Technologies: React, TypeScript, Rust, Git, Azure, Teams, JavaScript, PHP, Cursor AI, Claude Code, Streaming Data, WebSockets, TanStack Router, Software Development

Senior JavaScript Developer

2023 - 2023
Kerico Home Clinic Services LLC
  • Built a mobile app with React Native to handle patients' transportation.
  • Tracked and fixed bugs using the Sentry reporting tool.
  • Developed a web admin to manage users and drivers and eliminate manual work.
Technologies: Node.js, React, JavaScript, React Native, Sentry, AWS Command Line Interface (CLI), AWS Amplify, AmplifyJS, TypeScript, Front-end, Front-end Development, Web Development, Android, Testing, User Interface (UI), Mapbox, Mobile UX, Front-end Architecture, UI Components, NPM, Mobile First, Maps, MacBook, Git, User Experience (UX), Amazon Web Services (AWS), Software Development, Business Intelligence (BI)

Senior Front-end Engineer

2022 - 2023
Statement Mc
  • Developed a trading platform to exchange large quantities of food.
  • Built a pixel-perfect UI using Figma to showcase an intern product with Chakra UI.
  • Created an HR application to facilitate the company recruiting process.
Technologies: JavaScript, React, API Integration, Vercel, TypeScript, HTML, CSS, Chakra UI, APIs, Node.js, Marketplace Platforms, B2B, Responsive Design, Front-end, Front-end Development, Web Development, Next.js, Testing, ECMAScript (ES6), Auth0, User Interface (UI), Back-end Architecture, Prisma, Front-end Architecture, UI Components, NPM, Mobile First, MacBook, Git, User Experience (UX), Software Development, Supabase, Dashboards

Senior React Native Developer

2022 - 2022
The Skins App, Inc.
  • Refactored some style issues and improved the user experience for an innovative MVP app.
  • Helped find small things in the app to be able to release a better MVP.
  • Worked with GraphQL to reduce the amount of data coming from the server.
Technologies: React Native, GraphQL, Hasura, React, TypeScript, JavaScript, Git, GitHub, API Integration, JSX, APIs, Expo.io, Application State Management, Mobile App Development, CSS, Mobile Apps, Mobile Development, Front-end, Xcode, Testing, 3D, UI Components, NPM, MacBook, User Experience (UX), WebSockets, Software Development, Dashboards, Business Intelligence (BI)

React Native Developer

2022 - 2022
L`École AI, INC
  • Implemented the new React Native FlashList component to obtain more performance while rendering more than a 1000 images.
  • Created a custom function to fetch images from AWS S3 service and render them on the app.
  • Refactored some parts of the app and added TypeScript support.
  • Used the new Expo EAS Service to publish and share the app with the client.
Technologies: React Native, Expo, TypeScript, Amazon S3 (AWS S3), AWS Amplify, AmplifyJS, Amazon Web Services (AWS), Node.js, React, GitHub, JSX, APIs, Expo.io, Application State Management, Mobile App Development, CSS, JavaScript, Amazon Cognito, Mobile Apps, Mobile Development, Front-end, Front-end Development, Web Development, UI Components, MacBook, Git, User Experience (UX), Subscriptions, Software Development, Dashboards

React Front-end Developer

2022 - 2022
Toptal
  • Migrated a legacy UI to React with TypeScript and MUI, improving the codebase to consume the data from the server.
  • Developed an API and hosted it on Heroku to manage and connect it with the front end.
  • Migrated a trading advisory robot MVP (built with Python) that helps clients trade to a Node.js RESTful API.
Technologies: JavaScript, React, Python, Full-stack, Material UI, Node.js, Heroku, REST APIs, CSS, Responsive Web Apps, Front-end, GitHub, JSX, OAuth, APIs, Back-end Development, Application State Management, TypeScript, HTML, Responsive Design, Front-end Development, Web Development, Next.js, ECMAScript (ES6), User Interface (UI), Chart.js, Front-end Design, UI Components, NPM, MacBook, Git, User Experience (UX), WebSockets, Dashboards

Front-end Developer

2021 - 2022
Let's Delivery
  • Migrated the style codebase from Sass to styled-components and TypeScript.
  • Redesigned the entire app to a modern, pixel-perfect UI/UX based on Adobe XD designs.
  • Collaborated with the design team and used AWS S3 to share, test, and approve the new UI.
Technologies: React, Electron, React Redux, TypeScript, Sass, Styled-components, Atomic Design, React Query, REST, Bootstrap, GitHub, Amazon S3 (AWS S3), CSS, Storybook, API Integration, Jira, Trello, Scrum, Kanban, Responsive Web Apps, Front-end, JSON Web Tokens (JWT), JSX, APIs, Application State Management, HTML, JavaScript, Responsive Design, Front-end Development, Web Development, Next.js, ECMAScript (ES6), User Interface (UI), Front-end Design, NPM, MacBook, Git, User Experience (UX), WebSockets

Full-stack Developer

2020 - 2021
Hero99
  • Improved the performance and data sharing between nested components by adding RTK Query to fetch, cache, and update server data.
  • Added some custom utils React Hooks with TypeScript to a codebase resulting in less duplicated logic working with the Boolean data.
  • Improved components rendered by separating them into small ones.
Technologies: Axios, React Redux, NestJS, Google+ Authentication, MongoDB, TypeScript, JavaScript, Docker, Formik, React, Discord, Figma, MongoDB Atlas, Material UI, Node.js, Trello, Redux, Redux-Saga, Trello API, Scrum, REST APIs, Responsive Web Apps, Front-end, GitHub, JSX, APIs, Back-end, Back-end Development, Application State Management, HTML, CSS, Responsive Design, Front-end Development, SQL, Web Development, Next.js, User Interface (UI), Redux Toolkit, NPM, MacBook, Git, User Experience (UX), WebSockets

Front-end Developer

2020 - 2021
Spaceman
  • Automated the static page content editing process by connecting Contentful with the Next.js application.
  • Improved security in the DApp by adding a higher-order component (HOC) and server-side verification to check wallet connection and user permissions.
  • Wrote a Telegram bot in Node.js and Express.js to provide cryptocurrency information from the Ethereum network. Hosted it at Heroku.
Technologies: Axios, Contentful, Discord, Express.js, Git, GraphQL, JavaScript, Jest, Linux, GitHub, React, Next.js, Gatsby, React Testing Library, Ethers.js, Web3.js, Telegram Bot API, Heroku, Node.js, MetaMask, Styled-components, Emotion Library, Figma, Vercel, Telegram Bots, Tailwind CSS, Content Management Systems (CMS), REST APIs, CSS, Responsive Web Apps, Scrum, Redux, Front-end, JSX, Back-end Development, Application State Management, TypeScript, HTML, Unit Testing, Responsive Design, Front-end Development, Web Development, User Interface (UI), eCommerce, Blockchain, Web3, MacBook, User Experience (UX)

Front-end Developer

2019 - 2020
SNIR
  • Improved server data fetch, cache, and updates by using React Apollo and Axios to perform GraphQL requests.
  • Designed a new codebase for my entire team using Next.js, TypeScript, and GraphQL.
  • Improved a client global state management between nested components by adding a new React Context API.
Technologies: React, GraphQL, React Apollo, React Redux, Axios, TypeScript, Next.js, React Native, Formik, JavaScript, REST APIs, CSS, Bootstrap, Reactstrap, HTML, React Navigation, Context API, Jira, HTML5, CSS3, Redux, Responsive Web Apps, Front-end, JSON Web Tokens (JWT), GitHub, JSX, Azure, Azure DevOps, Apollo, Application State Management, Leadership, Responsive Design, Front-end Development, Web Development, User Interface (UI), MacBook, Git

Full-stack Engineer

2018 - 2019
Freelance | Self-employed
  • Developed a web application for an educational institution and automated their activities by 80%.
  • Built pixel-perfect web apps for small restaurants to manage their business.
  • Developed a startup website named Alien Space at 66alienspace.com.
Technologies: JavaScript, HTML, CSS, REST APIs, Responsive Web Apps, Node.js, MySQL, Redux, Front-end, React, React Native, JSON Web Tokens (JWT), GitHub, JSX, Back-end, Application State Management, Mobile App Development, TypeScript, PostgreSQL, Architecture, Chakra UI, React Native for Web, Mobile Apps, Firebase, Mobile Development, SQL, Web Development, Next.js, User Interface (UI), Payment Gateways, Git, Amazon Web Services (AWS)

Experience

Homus

https://homus.app
An AI-native real estate agent that acts as your co-pilot to rent out a property, handling payments, documents, and visits for you. Tenants talk with your agent so you don't have to, and answer any questions regarding your property. You just have to accept the tenant.

Skills

Libraries/APIs

React, Node.js, React Redux, React Query, Socket.IO, Stripe, REST APIs, Chart.js, GitHub API, React Native for Web, Formik, React Testing Library, Web3.js, Telegram Bot API, Context API, Reactstrap, React Navigation, Emotion Library, AWS Amplify, AmplifyJS, Redux-Saga, Trello API, YouTube API, Facebook API, Instagram API, TikTok API

Tools

Git, GitHub, Figma, Jira, JSX, Expo.io, Redux Toolkit, Prisma, NPM, Claude Code, TanStack Router, Expo, Trello, Notion, Slack, Auth0, Claude, React Apollo, MongoDB Atlas, MetaMask, Amazon Cognito, Sentry, AWS Command Line Interface (CLI), Xcode

Languages

TypeScript, JavaScript, GraphQL, HTML, CSS, SCSS, SQL, ECMAScript (ES6), Go, Sass, HTML5, CSS3, Python, Coolify, Rust, PHP

Frameworks

React Native, Express.js, Next.js, Material UI, Bootstrap, Tailwind CSS, Redux, JSON Web Tokens (JWT), Jest, NestJS, Electron

Paradigms

REST, Testing, UI Design, Web UI Design, Clean Code, Azure DevOps, Unit Testing, Marketplace Platforms, B2B, Mobile Development, Back-end Architecture, Scrum, Kanban, Business Intelligence (BI)

Platforms

Contentful, iOS, Visual Studio Code (VS Code), Docker, Vercel, Amazon Web Services (AWS), Azure, Android, Mapbox, Blockchain, Linux, Heroku, Netlify, Firebase

Storage

PostgreSQL, Databases, MongoDB, Redis, Amazon S3 (AWS S3), Hasura, MySQL

Other

MacBook, Styled-components, Full-stack, API Integration, Responsive Web Apps, WebSockets, Front-end, APIs, Apollo, Application State Management, Mobile App Development, User Interface (UI), User Experience (UX), Responsive Design, Front-end Development, Web Development, Dashboards, Front-end Architecture, Front-end Design, Mobile First, Full-stack Development, Responsive UI, AI Tools, Cursor AI, AI Integration, Streaming Data, Payment APIs, Software Development, Mobile UI, Supabase, Vibe Coding, Storybook, OAuth, Back-end, Back-end Development, Architecture, Mobile Apps, Mobile UX, Payment Gateways, eCommerce, 3D, UI Components, Web3, Maps, Subscriptions, Apple Pay, CI/CD Pipelines, OpenAI, Large Language Models (LLMs), JWT Authentication, Concurrency, Event-driven Systems, Software, Server Sent Events (SSE), Real Estate, Performance Optimization, Discord, Axios, Gatsby, Ethers.js, Google+ Authentication, Chakra UI, Domain-driven Design (DDD), Mirage, Webhooks, Prismic, Telegram Bots, Atomic Design, Content Management Systems (CMS), Leadership, Teams

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