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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

  • Sky Mavis
    React, Redux Toolkit, MUI (Material UI), Storybook, Ethers.js, MetaMask...
  • Scriber
    React, TypeScript, Recharts, Tailwindcss, GraphQL, Cypress.io, AWS Amplify...
  • VIVANT
    React, Redux, Socket.IO, LogRocket, Sentry, SCSS, AWS, React Testing Library...

Experience

Location

Elsa, United States

Availability

Full-time

Preferred Environment

VS Code, Slack, Jira, Zoom meeting, WebGL, REST, React Router, Server-side Rendering, Charts, Node.js, RESTful APIs, JavaScript Testing, Responsive Design

The most amazing...

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

Employment

  • Senior Front-end Engineer

    2021 - 2022
    Sky Mavis
    • Developed a blockchain-based NFT marketplace platform using React, Redux Toolkit, 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, AWS, Jest, Blockchain, Web3.js, Front-end Development, CSS3, HTML5, JavaScript, Redux, TypeScript, Cloud Services, Web Development, Zoom meeting, Jira, Slack, VS Code, Front-end, HTML, CSS, Webpack, Rollup.js, React Hooks, JSX, React Redux, Figma, Cryptocurrency, Analytics, Agile, APIs, GitHub, Git, CI/CD Pipelines, Web Animation, UI Animation, User Interface (UI), User Experience (UX), Amazon Web Services (AWS), Architecture, REST, React Router, Metrics, REST APIs, Server-side Rendering, RESTful APIs, Accessibility, JavaScript Testing, Behavior-driven Development (BDD), Responsive Design

  • Front-end Tech Lead

    2020 - 2021
    Scriber
    • Developed the all-in-one publishing tool for finance writers using React, Redux Toolkit, TypeScript, Recharts, Tailwind CSS for styling, 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 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, Recharts, Tailwindcss, GraphQL, Cypress.io, AWS Amplify, Storybook, E2E Testing, Unit Testing, Data Visualization, Mirco frontend architecture, Redux Toolkit, AWS, Enzyme, Front-end Development, Docker, CSS3, HTML5, JavaScript, Redux, Cloud Services, Web Development, Zoom meeting, Jira, Slack, VS Code, Front-end, HTML, CSS, Webpack, Rollup.js, React Hooks, JSX, React Redux, React Apollo, WebRTC, WebSockets, Tailwind CSS, Figma, Cryptocurrency, Analytics, Agile, Microsoft Teams, Teams, APIs, Financial Data, GitHub, Git, CI/CD Pipelines, MongoDB, Web Animation, UI Animation, User Interface (UI), User Experience (UX), Stripe, Amazon Web Services (AWS), Architecture, Meteor, REST, React Router, PostgreSQL, Metrics, REST APIs, Server-side Rendering, Charts, Node.js, RESTful APIs, Accessibility, Prismic, Chakra UI, JavaScript Testing, Behavior-driven Development (BDD), Responsive Design

  • 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, AWS, React Testing Library, Front-end Development, CSS3, HTML5, JavaScript, Web Development, Zoom meeting, Jira, Slack, VS Code, Front-end, HTML, CSS, Webpack, Rollup.js, React Hooks, JSX, React Redux, WebRTC, WebSockets, Figma, Analytics, Agile, Microsoft Teams, Teams, APIs, GitHub, Git, MongoDB, Web Animation, UI Animation, User Interface (UI), User Experience (UX), Stripe, Amazon Web Services (AWS), REST, React Router, PostgreSQL, Metrics, REST APIs, Server-side Rendering, Charts, RESTful APIs, Accessibility, Prismic, JavaScript Testing, Behavior-driven Development (BDD), Responsive Design

  • 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, GraphQL, Emotion, and Markdown.
    • Implemented the blog posts and details pages using 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, Contentful, Content Management Systems (CMS), CSS-in-JS, AWS, Styled-components, Next.js, Front-end Development, Docker, CSS3, HTML5, JavaScript, Redux, Cloud Services, Web Development, Zoom meeting, Jira, Slack, VS Code, MobX, Front-end, HTML, CSS, Webpack, JSX, React Redux, React Apollo, WebSockets, Figma, Analytics, Agile, APIs, GitHub, Git, Web Animation, UI Animation, User Interface (UI), User Experience (UX), Amazon Web Services (AWS), Internet Booking Engines (IBE), REST, React Router, Metrics, REST APIs, Charts, RESTful APIs, Accessibility, JavaScript Testing, Behavior-driven Development (BDD), Responsive Design, Headless Software

  • 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, AWS, React Testing Library, Next.js, Redux, TypeScript, React, Cloud Services, Web Development, Zoom meeting, Jira, Slack, VS Code, Context API, Front-end, HTML, CSS, Python, JSX, WebRTC, Analytics, Terraform, Microsoft Graph API, Vue, Nuxt.js, Quasar, Angular, NestJS, Web Animation, UI Animation, User Interface (UI), User Experience (UX), Mapbox, REST, React Router, Metrics, REST APIs, Server-side Rendering, Charts, Node.js, RESTful APIs, Accessibility, JavaScript Testing, Behavior-driven Development (BDD), Firebase Authentication, Responsive Design

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, 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.

Skills

  • Languages

    TypeScript, SCSS, Markdown, JavaScript, HTML5, CSS3, HTML, CSS, GraphQL, Python, Go

  • Frameworks

    MUI (Material UI), Redux, Next.js, Ant Design, Bootstrap, Cypress.io, Jest, Tailwind CSS, Nuxt.js, Svelte, Quasar, Angular, NestJS

  • Libraries/APIs

    React, Emotion Library, Context API, Node.js, React Redux, Stripe, React Router, REST APIs, Recharts, AWS Amplify, Socket.IO, Web3.js, D3.js, Highcharts, Chart.js, MobX, Rollup.js, WebRTC, Vue, WebGL

  • Tools

    JSX, GitHub, Git, JavaScript Testing, VS Code, Slack, Jira, MetaMask, Webpack, React Apollo, Figma, Terraform, Microsoft Teams, Apache, Firebase Authentication, Sentry

  • Paradigms

    REST, E2E Testing, Unit Testing, Agile, Behavior-driven Development (BDD)

  • Other

    Web Development, Storybook, Atomic Design, Data Visualization, Gatsby, Front-end Development, Styled-components, Semantic UI, Front-end, React Hooks, APIs, User Interface (UI), User Experience (UX), Architecture, Server-side Rendering, Charts, RESTful APIs, Prismic, Chakra UI, Responsive Design, Zoom meeting, Cloud Services, Redux Toolkit, Ethers.js, Tailwindcss, Mirco frontend architecture, React Testing Library, Enzyme, AWS, CSS-in-JS, Animation, WebSockets, Cryptocurrency, Analytics, Teams, Microsoft Graph API, Financial Data, CI/CD Pipelines, Web Animation, UI Animation, Internet Booking Engines (IBE), Metrics, Content Management Systems (CMS), Accessibility, Builder.io, Headless Software, LogRocket

  • Platforms

    Contentful, Blockchain, Docker, Firebase, Twilio, Azure, Amazon Web Services (AWS), Meteor, Mapbox

  • Storage

    MongoDB, 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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