Justin Villalpando, Developer in Elsa, TX, United States
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Justin Villalpando

Verified Expert  in Engineering

Front-end Developer

Location
Elsa, TX, United States
Toptal Member Since
May 16, 2022

Justin is a senior front-end architect with a broad and deep technological foundation. Over the last eight years, he gained experience dealing with various diverse tasks and challenging problems, including building front-end infrastructures and designing and optimizing numerous projects. Justin focuses on developing complete solutions from the ground up using modern JavaScript frameworks and blockchain technologies.

Portfolio

DocuSign Inc - Main
React, TypeScript, Storybook, Drupal, Netlify, Contentful, Figma, Atomic Design...
Airbnb
React, Redux, Next.js, TypeScript, GraphQL, Apollo, Styled-components...
Netflix
React, Context API, Netflix Hawkins, DataGrid, WebdriverIO, Storybook...

Experience

Availability

Part-time

Preferred Environment

Visual Studio Code (VS Code), Slack, Jira, Server-side Rendering (SSR), Charts, REST APIs, JavaScript Testing, Responsive Design, Accessibility, Sass

The most amazing...

...thing I've developed is the NFT marketplace called Axie Infinity, with 600,000+ users.

Work Experience

Front-end React Developer

2023 - 2023
DocuSign Inc - Main
  • Worked on reskinning the marketing platform according to the new design system and migrated Drupal 7 web contents into Contentful.
  • Built new reusable calligraphy components under atomic design pattern and pattern library components that interact with Contentful data.
  • Fixed some important production issues while working closely with customers and stakeholders and boosted the user experience to the next level.
Technologies: React, TypeScript, Storybook, Drupal, Netlify, Contentful, Figma, Atomic Design, Styled-components, Cypress, E2E Testing

Senior Front-end Engineer

2023 - 2023
Airbnb
  • Developed Pineapple, the world's most popular app for vacation homes and condo rentals, working as a senior front-end engineer.
  • Wrote unit testing using Jest and RTR on Storybook variations and E2E testing with Cypress, boosting test coverage by over 95%.
  • Worked on micro-frontend architecture for a monolithic front-end app, enabling the development of scalable and modular front-end systems.
  • Implemented data obfuscation functionality on the personal information page, enhancing security measures and accessibility.
  • Contributed to internationalization, supporting multiple languages and creating comprehensive technical documentation.
  • Fixed some customer-affecting production issues in the tight deadline, working closely with the customers and support team directly.
Technologies: React, Redux, Next.js, TypeScript, GraphQL, Apollo, Styled-components, JavaScript, CSS-in-JS, Formik, Webpack, Storybook, Jest, React Testing Library, Cypress, Amazon Web Services (AWS), Internalization, Accessibility, HTML5, CSS3

Senior Front-end Engineer

2022 - 2023
Netflix
  • Developed Ozark-UI, a supplier onboarding platform for Netflix using React, Context API, Hawkins—Netflix's internal UI framework—, DataGrid, Karbon for E2E testing, etc.
  • Built the reusable components using Hawkins and provided descriptive documentation with the examples in the storybook.
  • Troubleshot some important production bugs, boosted performance and code quality to the next level, and contributed to internationalization.
Technologies: React, Context API, Netflix Hawkins, DataGrid, WebdriverIO, Storybook, E2E Testing, Internationalization, Front-end, UX Design, Responsive Web Design (RWD), SDKs

Senior Front-end Engineer

2021 - 2022
Sky Mavis
  • Developed a blockchain-based NFT marketplace platform using React, Redux Toolkit, TypeScrpit, MUI, Storybook, Ethers.js, and MetaMask.
  • Introduced an atomic design with descriptive documentation using Storybook and configured its UI library and design system on the top of MUI using all the reusable components like atoms, molecules, and organisms.
  • Implemented breeding, hatching, buying, and selling functionalities leveraging Ethers.js blockchain technology.
  • Built a user-friendly filtering functionality and boosted the code quality and performance significantly.
Technologies: React, Redux Toolkit, Material UI, Storybook, Ethers.js, MetaMask, Atomic Design, CSS-in-JS, Blockchain, Front-end Development, HTML5, TypeScript, Cloud Services, Jira, Webpack, React Hooks, Figma, Git, REST APIs, Accessibility, Responsive Design, GitHub, APIs, HTML, CSS, Responsive Web Apps, Front-end, Non-fungible Tokens (NFT), Startups, UX Design, UI Design, Responsive Web Design (RWD), SDKs

Front-end Tech Lead

2020 - 2021
Scriber
  • Developed the all-in-one publishing tool for finance writers using React, Redux Toolkit, TypeScript, Next.js, Recharts, Tailwind CSS for styling, Apollo GraphQL, Cypress.io for E2E testing, AWS Amplify, and Storybook.
  • Acted as the front-end tech lead, mentored junior developers, and participated in making technical decisions at a high level.
  • Implemented an app authorization and data integration such as query and subscription using AWS Amplify and Apollo GraphQL.
  • Introduced a micro front-end architecture decomposing the project into individual and semi-independent micro apps working closely together.
  • Built the data visualization using Recharts and applied Storybook to expose reusable components with descriptive documentation.
  • Wrote the E2E test scripts using Cypress.io and boosted test coverage by over 90%.
Technologies: React, TypeScript, GraphQL, Cypress, AWS Amplify, Storybook, E2E Testing, Unit Testing, Data Visualization, Front-end Architecture, Amazon Web Services (AWS), Enzyme, Front-end Development, HTML5, JavaScript, Cloud Services, Webpack, React Hooks, Tailwind CSS, Figma, Git, Server-side Rendering (SSR), Behavior-driven Development (BDD), Responsive Design, Next.js, Apollo, GitHub, HTML, CSS, Responsive Web Apps, Front-end, Startups, Responsive Web Design (RWD), Amazon Cognito

Senior Front-end Engineer

2018 - 2020
VIVANT
  • Developed a virtual wine tasting platform using React, Redux Thunk, Socket.IO, LogRocket, Sentry, and SCSS.
  • Built various complex live session components focusing on maintainability and testability.
  • Implemented the lobby and wine tasting session screens utilizing Socket.IO and boosted user experience by introducing user-friendly animations and building mobile versions.
  • Followed the Scrum methodology using Asana while collaborating closely with the UX design and back-end teams.
Technologies: React, Redux, SCSS, Front-end Development, HTML5, JavaScript, Webpack, React Hooks, Figma, GitHub, Stripe, Amazon Web Services (AWS), Server-side Rendering (SSR), REST APIs, Accessibility, Responsive Design, Git, APIs, HTML, CSS, Responsive Web Apps, Front-end, Startups, Sass, Responsive Web Design (RWD)

Senior Front-end Engineer

2018 - 2018
Garden.io
  • Developed a marketing platform for Garden, which provides end-to-end development and testing services for Kubernetes and cloud using React, Gatsby, TypeScript, Apollo GraphQL, Emotion, and Markdown.
  • Implemented the blog posts and details pages using Apollo GraphQL, Contentful, and Markdown.
  • Boosted the project infrastructure, optimizing the performance and enhancing code quality to the next level.
  • Fixed some critical user experience issues on both desktop and mobile screens UI, keeping consistency across the different browsers.
Technologies: React, Gatsby, TypeScript, GraphQL, Emotion Library, Markdown, CSS-in-JS, Styled-components, Docker, HTML5, JavaScript, Cloud Services, Jira, Webpack, Figma, Git, Amazon Web Services (AWS), Accessibility, Responsive Design, Apollo, GitHub, HTML, CSS, Responsive Web Apps, Front-end, Responsive Web Design (RWD)

Junior Front-end Engineer

2015 - 2018
Cognitus Consulting
  • Oversaw the building of pixel-perfect and mobile-friendly UI/UX of various web applications and API integrations.
  • Improved the design and performance of writing the code in a high-paced and challenging environment, emphasizing the best practices.
  • Worked actively in Agile and Scrum environments with 2-week sprints.
Technologies: JavaScript, HTML5, CSS3, Front-end Development, Chart.js, Highcharts, Animation, CSS-in-JS, Bootstrap, Semantic UI, Ant Design, D3.js, Amazon Web Services (AWS), React Testing Library, Next.js, Redux, TypeScript, React, Cloud Services, Jira, Context API, User Interface (UI), User Experience (UX), Node.js, REST APIs, Accessibility, Responsive Design, MobX, GitHub, Git, APIs, HTML, CSS, Responsive Web Apps, Front-end, Sass, UI Design, Responsive Web Design (RWD), Express.js

Axie Infinity | NFT marketplace

Axie Infinity is a blockchain-based NFT marketplace platform.

I developed it using React, Redux Toolkit, Material-UI, Storybook, Ethers.js, and MetaMask. I also introduced an atomic design with descriptive documentation using Storybook and configured its UI library and design system on the top of Material UI. With the user-friendly filtering functionality and improved code, the performance was boosted significantly.

Scriber | Publishing Tool for Finance Writers

https://scriber.to
Scriber is an all-in-one publishing tool for finance writers.

As a front-end lead, I developed it using React, Redux Toolkit, TypeScript, Next.js, Recharts, Tailwind CSS for styling, GraphQL, Cypress.io for E2E testing, AWS Amplify, and Storybook. I also implemented an app authorization and data integration, introduced a micro-frontend architecture, built the data visualization, wrote E2E test scripts, and boosted test coverage by 90%.

VIVANT | Virtual Wine Tasting and Organic Wine

https://vivant.eco/
A virtual wine tasting platform developed with React, Redux Thunk, Socket.IO, LogRocket, Sentry, and SCSS.

I built complex live session components while ensuring maintainability and testability, implemented the lobby and wine tasting session screens, and introduced user-friendly animations and mobile versions, improving user experience.

Garden.io | Market Platform

https://garden.io/
Garden is an end-to-end cloud delivery platform that accelerates the client's development, testing, and CI/CD workflows.

I developed it with React, Gatsby, TypeScript, GraphQL, Emotion, and Markdown, implemented the blog posts and details pages, boosted the project infrastructure, optimized the performance, and enhanced code quality. I also fixed critical user experience issues on desktop and mobile UI, keeping consistency across the different browsers.

ATD Org | Education and E-learning Platform

https://td.org
ATD is the world's largest talent development platform.

I built this platform using React, Apollo GraphQL, TypeScript, Material UI, and Algolia, leveraging an atomic design. Built a reusable ATD component library using React, Material UI, TypeScript, and Styleguidist and published them into the cloud using bit.dev. Worked on TDD strategy writing testing scripts using Jest/Enzyme.

Heycar | Car Marketplace

https://heycar.com
Heycar is one of the most famous car marketplaces in the EU.

I worked as a founding front-end engineer at Heycar, building a car marketplace platform from scratch using React, Next.js, TypeScript, and Storybook, and contributed to architecting the project structure. Wrote unit testing using React testing library and implemented internationalization using the React-intl library. Built reusable components and exposed the examples in the storybook, and developed a bunch of custom hooks for various purposes.
2010 - 2014

Master's Degree in Computer Science

The University of Texas at Austin - Austin, Texas, USA

APRIL 2016 - PRESENT

React Certified Engineer

Sololearn

MARCH 2016 - PRESENT

JavaScript Certified Engineer

Sololearn

Libraries/APIs

React, Emotion Library, Context API, Node.js, React Redux, Stripe, REST APIs, AWS Amplify, Web3.js, React Testing Library, D3.js, Highcharts, Chart.js, MobX, Formik

Tools

Git, GitHub, Jira, Redux Toolkit, MetaMask, Webpack, Figma, Amazon Cognito, WebdriverIO

Frameworks

Material UI, Redux, Next.js, Ant Design, Bootstrap, Cypress, Jest, Tailwind CSS, Express.js

Languages

TypeScript, GraphQL, SCSS, Markdown, JavaScript, HTML5, CSS3, HTML, CSS, Sass

Paradigms

Responsive Web Design (RWD), E2E Testing, Unit Testing, Behavior-driven Development (BDD), UX Design, UI Design

Storage

PostgreSQL

Platforms

Blockchain, Docker, Amazon Web Services (AWS), Drupal, Netlify, Contentful

Other

Storybook, Atomic Design, Data Visualization, Gatsby, Front-end Development, Styled-components, Semantic UI, React Hooks, User Interface (UI), User Experience (UX), Server-side Rendering (SSR), Charts, Chakra UI, Responsive Design, APIs, Responsive Web Apps, Front-end, Startups, Cloud Services, Ethers.js, Front-end Architecture, Enzyme, CSS-in-JS, Animation, Accessibility, Apollo, Non-fungible Tokens (NFT), SDKs, ESLint, Internalization, Netflix Hawkins, DataGrid, Internationalization

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