Leo Fabrikant, Software Developer in Boston, United States
Leo Fabrikant

Software Developer in Boston, United States

Member since August 18, 2022
Leo is a web front-end technology expert in React and TypeScript with extensive back-end experience with Node.js, Next.js, and Python. Technology stacks are one of the business's most important choices, and Leo prioritizes thoroughly understanding the trade-offs that all popular and effective web technologies make. Leo chooses the best tool for the job to maximize performance and code quality for whatever tech stack he works on.
Leo is now available for hire


  • Constant Contact
    React, TypeScript, GraphQL, Node.js, HTML, CSS, React Apollo, MobX
  • Isobar
    React, JavaScript, Redux, AWS Lambda, Node.js, HTML, CSS



Boston, United States



Preferred Environment


The most amazing...

...solution I've built was a complex UI and algorithm for a drag-and-drop branching workflow canvas maintaining even spacing between user-generated nodes.


  • Lead Software Engineer

    2020 - 2022
    Constant Contact
    • Introduced unique type safe workflow across a GraphQL API and front end, allowing the front end to be synced with types generated on the back end.
    • Built a library for creating a complex branching workflow canvas, allowing drag and drop of nodes while maintaining even spacing between them. Designed an algorithm to manage the node spacing. Published it as the organization's private npm package.
    • Evaluated and introduced many new technologies to the company tech stack as was requested. Assessed new technologies to potentially adopt company-wide. Technologies include TypeScript, Recoil, and GraphQL.
    Technologies: React, TypeScript, GraphQL, Node.js, HTML, CSS, React Apollo, MobX
  • Senior Front-end Engineer

    2018 - 2020
    • Led a front-end team on a new initiative to provide a car and driver service in China. Built a full reservation flow, including location inputs integrated with mapping APIs. Helped deploy AWS Lambda API layer built using Node.js.
    • Upgraded and maintained a high-traffic enterprise web app. Led initiatives and managed junior developers. Spearheaded an upgrade to React 15 and 16 and refactored an old app-state-management system to use Redux.
    • Re-designed site-wide modal control architecture using React-modal to be more generic, composable, and easier to implement.
    Technologies: React, JavaScript, Redux, AWS Lambda, Node.js, HTML, CSS


  • Participation Reports

    A simple UI for searching and evaluating scientific organizations. It includes a uniquely challenging search interface as it allows a predictive search of tens of thousands of organizations done on the front end. I used extensive performance profiling and advanced technologies like web workers to identify and resolve issues. As a result, it is a very fast, highly performant predictive search feature.

  • Transpose Scholarly Records Database

    Created a web app to search through databases of scholarly journals using React Hooks. Also, I integrated with Google API to generate data from Google Sheets. Finally, I developed a custom content management system.


  • Languages

    TypeScript, JavaScript, HTML, CSS, Python, GraphQL
  • Libraries/APIs

    React, Node.js, MobX
  • Frameworks

    Next.js, Redux, Django
  • Tools

    React Apollo
  • Storage

    PostgreSQL, MySQL
  • Paradigms

    Web App Design
  • Platforms

    Amazon Web Services (AWS), AWS Lambda, Web
  • Other

    Analysis, Programming, Web Development


  • Certification in Web Design Concepts
    JULY 2022 - PRESENT
  • Certified Programmer/Analyst Aptitude
    JULY 2022 - PRESENT
  • Master Certification in CSS3
    JULY 2022 - PRESENT
  • Certification in JavaScript 1.8
    JULY 2022 - PRESENT

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