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Justin Villalpando, Front-end Developer in Elsa, United States
Justin Villalpando

Front-end Developer in Elsa, United States

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 the 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.
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Portfolio

  • Netflix
    React, Context API, Netflix Hawkins, DataGrid, WebdriverIO, Storybook...
  • Sky Mavis
    React, Redux Toolkit, MUI (Material UI), Storybook, Ethers.js, MetaMask...
  • Scriber
    React, TypeScript, GraphQL, Cypress, AWS Amplify, Storybook, E2E Testing...

Experience

Location

Elsa, United States

Availability

Full-time

Preferred Environment

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

The most amazing...

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

Employment

  • 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)

  • 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, MUI (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, UI Animation, React Router, 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)

  • 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, WebSockets, Tailwind CSS, Figma, Analytics, Financial Data, Git, React Router, 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)

  • 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, Socket.IO, LogRocket, Sentry, SCSS, Front-end Development, HTML5, JavaScript, Web Development, Webpack, Rollup.js, React Hooks, WebRTC, Figma, Analytics, GitHub, UI Animation, Stripe, Amazon Web Services (AWS), React Router, 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, Content Management Systems (CMS), Contentful, CSS-in-JS, Styled-components, Docker, HTML5, JavaScript, Cloud Services, Web Development, Jira, Webpack, Figma, Analytics, Git, Web Animation, 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, Azure, Bootstrap, Semantic UI, Ant Design, D3.js, Twilio, Firebase, Amazon Web Services (AWS), React Testing Library, Next.js, Redux, TypeScript, React, Cloud Services, Web Development, Jira, Context API, Analytics, User Interface (UI), User Experience (UX), Mapbox, REST, React Router, Node.js, REST APIs, Accessibility, Responsive Design, MVC Frameworks, MobX, GitHub, Git, APIs, HTML, CSS, Responsive Web Apps, Front-end, Sass, UI Design, Responsive Web Design (RWD)

Experience

  • 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.

Skills

  • Languages

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

  • Frameworks

    MUI (Material UI), Redux, Next.js, Ant Design, Bootstrap, Cypress, Jest, Tailwind CSS

  • Libraries/APIs

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

  • Tools

    Git, GitHub, Jira, MetaMask, Webpack, Figma, WebdriverIO

  • Paradigms

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

  • 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, Redux Toolkit, Ethers.js, Front-end Architecture, React Testing Library, Enzyme, CSS-in-JS, Animation, Accessibility, Apollo, Non-fungible Tokens (NFT), ESLint, Internalization, Netflix Hawkins, DataGrid, Internationalization

  • Platforms

    Blockchain, Docker, Amazon Web Services (AWS)

  • Storage

    PostgreSQL

Education

  • Master's Degree in Computer Science
    2010 - 2014
    The University of Texas at Austin - Austin, Texas, USA

Certifications

  • React Certified Engineer
    APRIL 2016 - PRESENT
    Sololearn
  • JavaScript Certified Engineer
    MARCH 2016 - PRESENT
    Sololearn

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