Brendan O'Brien, React Developer in Alvor, Portugal
Brendan O'Brien

React Developer in Alvor, Portugal

Member since November 21, 2020
Brendan is a software developer with an expert skillet that includes React Native, TypeScript, GraphQL, and Node.js. He's built four minimum viable products (MVPs) using React Native and Node.js for early-stage startups, most recently for Mavely ( Brendan excels at rapid prototyping and is passionate about bringing life to visions and ideas while meeting deadlines.
Brendan is now available for hire


  • Mavely
    React, React Native for Web, Firebase, Apollo Server, Docker, Google Cloud...
  • Yotta Workout
    React, React Native for Web, Node.js, Firebase, Expo, Redux, React Native
  • The Bet Excahnge
    Node.js, Ruby on Rails (RoR), Expo, Redux, React Native



Alvor, Portugal



Preferred Environment

React, Redux, Firebase, Expo, Node.js, GraphQL, React Native for Web, React Native, TypeScript

The most amazing...

...thing I've developed is Mavely, where users can earn cash from home by shopping and selling female-founded and sustainable brands. Check it out at


  • React Native/TypeScript Developer

    2018 - 2020
    • Joined as the first engineer to rapidly prototype and get the company going by building an MVP with React Native. This helped transition the company to the current stack as the it grew.
    • Incorporated intelligent deep linking among the mobile app, web app, and Shopify to help create a community of over 15,000 entrepreneurial women across the US—earning up to $5,000 in extra cash per year by sharing these links on social media.
    • Integrated products, images, and more with GraphQL from over 200 retail partners including Everlane, Brooklinen, Allbirds, Outdoor Voices, Sun Basket, ABLE, and hundreds more within the mobile app to create an ideal social eCommerce experience.
    Technologies: React, React Native for Web, Firebase, Apollo Server, Docker, Google Cloud, Prisma, Node.js, GraphQL, React Native, TypeScript
  • Lead Software Engineer

    2018 - 2020
    Yotta Workout
    • Built out the entire app infrastructure (as a solo developer) with both React Native on the front end and Node.js/Firebase on the back end—bringing 100s of hours of mindfulness content in a streamlined, gamified interface that is both interactive and calming.
    • Implemented a premium subscription service to provide dynamic media content within the mobile app, including low-impact cardio, yoga videos, and mental training to paying customers.
    • Oversaw the launch process of the iOS and Android app, which can be found at
    Technologies: React, React Native for Web, Node.js, Firebase, Expo, Redux, React Native
  • Lead Application Developer

    2018 - 2020
    The Bet Excahnge
    • Built the app from scratch using designs from Zeplin and worked closely with the CTO to interface with his Ruby on Rails back end.
    • Integrated charts and data visualization using React Native SVG to create a detailed UI to represent betting/sporting data.
    • Tested the app with real-time data using WebSockets to help explore the future of fantasy e-sports by allowing users to places dynamic bets on futures within sports, much like traders do on stocks.
    Technologies: Node.js, Ruby on Rails (RoR), Expo, Redux, React Native
  • Co-founder | VP of Engineering

    2016 - 2018
    Brainbuild,, Inc.
    • Built the whole product from the ground up using AngularJS and Node.js, eventually migrating to React and React Native. Hired two more full-stack JavaScript developers that I managed by building out weekly sprints while still programming myself.
    • Oversaw the entire engineering team as Brainbuild grew to be an Inc. Top 30 Emerging Companies in the US:
    • Integrated an automated nutrition-and-health scheduling machine learning algorithm within the iOS and Android mobile apps. This algorithm optimizes the timing of meals, snacks, hydration, and sleep events based on a person's unique daily schedule.
    Technologies: Amazon Web Services (AWS), AngularJS, MongoDB, AWS, Firebase, Node.js, Expo, Redux, React Native
  • Web Developer

    2015 - 2015
    • Leveraged various front-technologies (HTML, CSS, JavaScript, jQuery) to graph/tabulate company data on an enterprise website.
    • Implemented a PHP/ database (back end) to compile company statistics.
    • Utilized these statistics to better understand how to get the perfect music at every location, whether it be a gym, restaurant, or business center—
    Technologies: CSS, HTML, JavaScript


  • Mavely

    Users earn cash by supporting thousands of female-founded, sustainable, and “good for the world” products, curated just for them. It has over 200 retail partners including Everlane, Brooklinen, Allbirds, Outdoor Voices, Sun Basket, True Botanicals, ABLE, and hundreds more.


  • Languages

    TypeScript, JavaScript, HTML, GraphQL, Java, C, Assembly
  • Frameworks

    React Native, Redux, AngularJS
  • Libraries/APIs

    Node.js, React, React Native for Web
  • Tools

    Expo, Prisma, MATLAB
  • Platforms

    Firebase, Docker, Amazon Web Services (AWS)
  • Storage

    Google Cloud, MongoDB
  • Other

    AWS, Apollo Server


  • Bachelor's Degree in Biomedical Engineering/Electrical and Computer Engineering | Minor: Computer Science
    2012 - 2016
    Duke University - Durham, NC, United States

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