André is available for hire
Hire AndréAndré Castelo
Verified Expert in Engineering
JavaScript Developer
João Pessoa, Paraíba - State of Paraíba, Brazil
Toptal member since August 29, 2016
Bio
André is a software engineer focusing on front-end development, with years of experience building JavaScript applications using React. He has also worked on several full-stack projects using PHP and Python, leveraging tools such as Laravel, Django, and FastAPI to deliver quality products.
Portfolio
Parade
TypeScript, React, Next.js, Python, FastAPI, Django, Django REST Framework...
finmid
React, Redux, TypeScript, Node.js, Express.js, Redux-Saga, Formik, Terraform...
Gartner - Digital Markets Engineering - Non-Capitalizable
React, Tailwind CSS, Styled-components, Microfrontends, A/B Testing, HTML5...
Experience
- JavaScript - 8 years
- Mobile Web - 6 years
- Python - 4 years
- Material UI - 4 years
- Redux - 3 years
- TypeScript - 2 years
- React - 2 years
- FastAPI - 1 year
Preferred Environment
Git, MacOS, Neoim Text Editor, Tmux
The most amazing...
...project I worked on was an AI-based email dispatcher that allowed trucking companies to ask for loads by email and get them automatically.
Work Experience
Senior Software Engineer
2022 - PRESENT
Parade
- Improved the performance of the web platform by reducing the time it takes for the pages to load from six seconds to less than one second.
- Built features for a major flagship AI product with Python (FastAPI) and integrated with Google PubSub and ChatGPT. Improved our clients' responses to opportunities and increased their digital transactions on average from 10% to 35%.
- Built an API to consume public government data and provide information on trucking companies. This API was responsible for significantly speeding up the sales pipeline in the following months.
- Implemented single sign-on to work with clients' custom identity providers, which led to increased ARR via three big enterprise clients signing up with the company.
- Worked closely with the customer support team to address client issues and fix eventual bugs.
Technologies: TypeScript, React, Next.js, Python, FastAPI, Django, Django REST Framework, SQLAlchemy, PostgreSQL, PostGIS, Docker, CircleCI, GitHub Actions, Redux, Formik, Material UI, APIs, CSS, Firebase, HTML, Styled-components, Continuous Integration (CI), Front-end, Node.js, REST APIs, MERN Stack, Large Language Models (LLMs), Auth0, Single Sign-on (SSO), Full-stack, Storybook, HTML5
Senior Software Engineer
2021 - 2022
finmid
- Architected and built from the ground up the main front-end dashboard using TypeScript, React, and Redux, as well as maintaining the Terraform and Docker configurations for the front-end applications.
- Wrote end-to-end tests using the Playwright library, also using them to monitor stability and availability of the production environment with smoke tests.
- Integrated Keycloak authentication (PKCE) in our main application, with multi-tenancy support in the front end. Different clients would provide different auth realms to their users.
- Monitored and fixed issues using a combination of Sentry and Kibana, with Linear as our reporting tool.
- Architected and built from the ground up our platform dashboard and platform gateway service. The gateway was in charge of communicating with the Kotlin back end and preventing complex logic from being added to the front end.
- Built and maintained internal packages used by our front-end team to improve consistency across our multiple front-end applications.
- Mentored our junior front-end developers with code reviews and pair programming.
- Documented the apps and libraries extensively using Notion and markdown files in our codebase, iterating on those to improve onboarding of new developers, asynchronous communication, and developer experience.
Technologies: React, Redux, TypeScript, Node.js, Express.js, Redux-Saga, Formik, Terraform, Docker, Material UI, Playwright, E2E Testing, RTK Query, Kibana, Sentry, Grafana, GitHub Actions, Continuous Deployment, Continuous Integration (CI), Yarn Workspaces, Monorepos, Keycloak, Notion, CSS, HTML, Styled-components, APIs, Front-end, REST APIs, MERN Stack, PostgreSQL, Full-stack, Storybook, HTML5
React Developer
2021 - 2021
Gartner - Digital Markets Engineering - Non-Capitalizable
- Improved search performance by refactoring React components to use Tailwind CSS.
- Implemented A/B tests according to specifications from the product team.
- Fixed errors in A/B tests and ensured the correct hypothesis was being tested.
Technologies: React, Tailwind CSS, Styled-components, Microfrontends, A/B Testing, HTML5, Responsive Web Design (RWD)
Senior Front-end Developer
2020 - 2020
Cyral Inc
- Developed and iterated over the design for several pages and components, focusing on making the interface easier for users while also making it look good.
- Implemented Emotion, a CSS-in-JS library, into the project to improve the organization and readability of the CSS code for the project.
- Added code quality enforcing tools to ensure that the codebase had a consistent style and that no syntax errors were committed.
Technologies: Mobile Web, User Interface (UI), User Experience (UX), Material UI, Emotion Library, React, JavaScript, Keycloak, CSS, HTML, Styled-components, Front-end, HTML5
Senior Front-end Developer
2020 - 2020
Rain
- Implemented a complete redesign of the client's dashboard, focusing on component reusability and readability while ensuring it closely matched the design.
- Implemented the CSS-in-JS library Emotion to help organize the styling and minimize repeated code as much as possible.
- Worked with other developers to create an appropriate style guide for the codebase and used Git hooks and other tools to enforce it.
Technologies: Mobile Web, JavaScript, Emotion Library, React, CSS, HTML, Front-end, HTML5
Front-end Developer
2019 - 2020
Coolfire Solutions
- Implemented several components according to specifications and worked closely with the designer to make sure they matched the InVision designs.
- Worked on a client's dashboard, where the user was able to create data streams and manage their networks with ease.
- Made several improvements to UX to make the dashboard as intuitive as possible.
- Worked closely with the other developers reviewing code, writing tests, and fleshing out front-end architecture.
Technologies: Mobile Web, TypeScript, JavaScript, Styled-components, Apollo, GraphQL, React, CSS, HTML, Front-end, Tailwind CSS, HTML5, Responsive Web Design (RWD)
Senior Front-end Developer
2019 - 2019
Vault Health
- Implemented many components related to their website redesign, focusing on responsive design and ensuring the layout was pixel perfect in all of the required resolutions.
- Restructured their patient information quiz to allow the marketing team to deploy different quizzes and A/B test them for optimal engagement.
- Worked closely with the designer and the other developers to ensure a quality delivery.
Technologies: Mobile Web, JavaScript, Emotion Library, TypeScript, Redux, React, CSS, HTML, HTML5
Front-end Developer
2018 - 2019
Listing Loop
- Created several high-fidelity React components according to the design approved by the client.
- Refactored several existing components and created new ones to ensure the platforms were compatible with mobile.
- Improved performance on several areas of the application by simplifying code, implementing pagination, and extracting components.
Technologies: Mobile Web, JavaScript, Firebase, Rollup, TypeScript, Redux-Saga, Redux, React, CSS, HTML, APIs, Front-end, MERN Stack, HTML5, Responsive Web Design (RWD)
Web Developer
2017 - 2018
Grin, Inc.
- Worked on a feature to create email sequences that are automatically sent based on current relationship status with an influencer.
- Implemented scheduled jobs to send pending campaign emails.
- Maintained the front and back end and fixed bugs.
Technologies: PHP, JavaScript, MySQL, Elasticsearch, Forge, Envoyer, Vue, Laravel, PHP 7, HTML, APIs, Front-end, SCSS, Full-stack, HTML5
Back-end Developer
2017 - 2017
Daring Development
- Created the API test suite with HTTP and unit tests as well as tests for the most critical parts of the application.
- Integrated the API with Discord—every time a new pro user registers on our application, we add him to the correct Discord server with the correct roles and username. This was achieved using the Laravel scheduler, Socialite, and the Discord API.
- Overhauled the way users vote for which games they want cheats for.
- Worked completely in the back end with Laravel 5.4.
Technologies: PHP, MySQL, Laravel, PHP 7, APIs, REST APIs, Full-stack, HTML5
PHP/JavaScript Developer
2016 - 2017
ContentLaunch (via Toptal)
- Worked on getting Twitter, Facebook, WordPress, Writer Access, and Stripe integrations up and running.
- Integrated the app with Amazon S3.
- Implemented the accounts feature, making it easier for users to collaborate with each other on content while allowing agencies to better handle their business accounts.
Technologies: PHP, JavaScript, Vue, Sass, Laravel, PHP 7, CSS, HTML, APIs, Front-end, REST APIs, SCSS, Full-stack, HTML5
Web Developer
2016 - 2016
WPensar Group
- Worked closely with designers and other developers to deliver top quality interfaces.
- Created an end-to-end testing suite using Behave and Selenium to ensure the quality of the user experience.
- Wrote endpoints for our API to deliver new functionality for our customers.
- Wrote a unit testing suite for our front-end application to guarantee the consistency and quality of critical features.
- Optimized the front-end build pipeline using Gulp.js, JavaScript linters, and the TypeScript compiler.
Technologies: JavaScript, Gulp, TypeScript, AngularJS, MySQL, Django REST Framework, Python, Django, CSS, HTML, APIs, Front-end, SCSS, Full-stack, HTML5, Responsive Web Design (RWD)
Web Developer and Software Architect
2013 - 2016
Estrategia Marketing Digital
- Worked on several legacy CodeIgniter projects, keeping them up to date and modernizing the codebase.
- Deployed multiple PHP applications written in Laravel and CodeIgniter.
- Developed RESTful APIs using CodeIgniter and Laravel.
- Worked closely with designers to deliver innovative interfaces and experiences.
- Planned and implemented architecture and databases for several clients.
Technologies: MySQL, Mobile Web, Vue, jQuery, JavaScript, Grunt, Gulp, PHP, Sass, AngularJS, Laravel, CSS, HTML, APIs, Front-end, REST APIs, SCSS, Full-stack, HTML5, Responsive Web Design (RWD)
Experience
Vault Health
https://www.vaulthealth.com/Vault Health delivers a unique solution to health issues that plague men of all ages. I was involved in the redesign of their main website, as well as implementing some key functionalities related to their patient care dynamic forms.
The project was built using React, Redux, TypeScript, and some CSS-in-JS using Emotion.
The project was built using React, Redux, TypeScript, and some CSS-in-JS using Emotion.
Listing Loop Platform
https://www.listingloop.com.au/Listing Loop aimed to connect buyers and real estate agents in the Australian market with a unique approach. The UI and UX were a great challenge, involving responsive design, maps, dynamic components, and a lot of interaction.
The tech stack consisted of React, Redux, TypeScript, Styled System and Styled Components, and Firebase in the back end. There were many challenges with data handling, responsiveness, and overall polishing, and I'm really proud of the work I've done on this project.
The tech stack consisted of React, Redux, TypeScript, Styled System and Styled Components, and Firebase in the back end. There were many challenges with data handling, responsiveness, and overall polishing, and I'm really proud of the work I've done on this project.
Grin, Inc.
http://www.grin.coGrin is a platform that connects social media influencers and marketing teams, tracks their relationships and compensations, and allows those teams to move quickly and efficiently with their influencer marketing projects.
While working on this project, I touched several layers of the stack—from the back end with PHP and Laravel, setting up microservices and integrating them, to developing responsive components using Vue and Vuex. I'm proud of the work I did for Grin and happy that the solutions implemented accelerated the company's growth.
While working on this project, I touched several layers of the stack—from the back end with PHP and Laravel, setting up microservices and integrating them, to developing responsive components using Vue and Vuex. I'm proud of the work I did for Grin and happy that the solutions implemented accelerated the company's growth.
Education
2011 - 2011
Post-graduate Coursework in Web Development
Pontífice Universidade Católica do Rio de Janeiro - Rio de Janeiro, Brazil
2005 - 2010
Bachelor's Degree in Computer Science
Federal University of Paraíba - Paraíba, Brazil
Skills
Libraries/APIs
React, Vue, jQuery, Node.js, REST APIs, Redux-Saga, Emotion Library, Facebook API, X (formerly Twitter) API, Stripe API, Formik, Playwright, SQLAlchemy
Tools
Gulp, Webpack, Git, PhpStorm, PyCharm, Grunt, Envoyer, Rollup, Terraform, RTK Query, Kibana, Sentry, Grafana, Yarn Workspaces, Keycloak, Notion, CircleCI, Neoim Text Editor, Tmux, Auth0
Languages
PHP, JavaScript, TypeScript, HTML, CSS, HTML5, Python, Sass, SCSS, PHP 7, GraphQL
Frameworks
Laravel 5, Material UI, Redux, Next.js, AngularJS, Laravel, Django REST Framework, Django, Express.js, Tailwind CSS
Paradigms
Responsive Web Design (RWD), Agile Software Development, E2E Testing, Continuous Deployment, Continuous Integration (CI), Microfrontends
Platforms
Linux, Ubuntu, Firebase, Mobile, MacOS, Docker, Visual Studio Code (VS Code)
Storage
MySQL, Elasticsearch, PostgreSQL, PostGIS
Other
Front-end, Full-stack, Mobile Web, FastAPI, APIs, MERN Stack, Forge, Apollo, Styled-components, User Experience (UX), User Interface (UI), Computer Science, Web Development, GitHub Actions, Monorepos, Large Language Models (LLMs), A/B Testing, Single Sign-on (SSO), Storybook
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