Ken Fehling, Front-end Developer in Honolulu, United States
Ken Fehling

Front-end Developer in Honolulu, United States

Member since August 19, 2022
Ken is a full-stack developer with a focus on front-end development with React. He has over 10 years of experience in web dev with HTML/CSS/JavaScript and 7 years with React and Redux. On the back end, he has primarily worked with Node.js, Django, Flask, and SQL databases like PostgreSQL, MySQL, and SQLite. Although not a designer, Ken has worked on UI/UX for several front-end web and mobile projects with UI frameworks like Bootstrap and Material UI and from scratch with CSS and Sass.
Ken is now available for hire




Honolulu, United States



Preferred Environment

React, Redux, HTML, CSS, JavaScript, TypeScript, Python, Web Development, D3.js, Web

The most amazing...

...application I've developed is a dashboard for data visualization using a React and D3.js front end and a Django and PostGIS back end.


  • Jinja2/HTML/CSS Developer | Data Engineering App

    2022 - PRESENT
    Orita Inc.
    • Implemented a new front end based on Figma designs for AI business SaaS customers.
    • Created Jinja2 templates using Tailwind CSS and JavaScript with a Python and Flask back end.
    • Worked with the designer, suggesting improvements to the UI/UX.
    Technologies: HTML, CSS, Jinja, JavaScript, Python, Flask, Tailwind CSS
  • Front-end React Developer

    2022 - PRESENT
    Solvent Holdings Corp (via Toptal)
    • Implemented a new reporting interface, including graphs, tables, and customized filter components.
    • Refactored legacy React class-based components to function components with hooks.
    • Reduced the number of component re-renders, improving performance and user experience.
    • Introduced Storybook to the project and used it for newly created components.
    Technologies: Front-end, JavaScript, React, Python, Django, PostgreSQL, Data Visualization, D3.js, Chart.js, Redux, Storybook, React Final Form, React Redux, HTML5, Git, Kanban, React Router, JSX, NPM, Web Development, Web, Web Pages, Single-page Applications (SPA), HTML DOM, UI Design, Web UI Design, User Experience (UX)
  • Web Developer

    2014 - 2022
    • Worked on many full-stack projects, from design to back end.
    • Used D3.js and visx to create interactive web-based data visualizations.
    • Created a custom CMS and static site generator for freelance clients based on Django, Django admin, and Django-distill.
    Technologies: JavaScript, HTML, CSS, React, Redux, Django, PostgreSQL, SQL, PostGIS, Pandas, NumPy, Node.js, TypeScript, React Native, Express.js, Kotlin, SQLite, Lodash, HTML5, Sass, Flask, React Router, FFmpeg, Front-end, Relational Databases, Relational Database Design, Full-stack, Git, GitHub, GitHub Pages, Functional Programming, MongoDB, Mongoose, Data Visualization, APIs, REST, REST APIs, Software, Software Engineering, jQuery, React DnD, JSX, Gatsby, Next.js, Bootstrap, Bootstrap 4, Bash, Bash Script, Shell, Shell Scripting, MERN Stack, Python, Docker, Trello, MySQL, Jinja, Storybook, 2D Games, Netlify, Vercel, Web Development, Databases, Raspberry Pi, React Motion, Responsive Design, Google Cloud Platform (GCP), Google Cloud, Adobe Illustrator, Vector Graphics, PiLLoW, PIL, Image Processing, Python 3, Django ORM, Front-end Development, Web Scraping, Dynamic Websites, Web App Design, Web, GUI, Back-end, Web Pages, Responsive UI, User Interface (UI), Web UI, Web UX, DigitalOcean, Search Engine Optimization (SEO), Amazon Web Services (AWS), Visual Studio Code, Single-page Applications (SPA), Redux Thunk, HTML DOM, MUI (Material UI), React Redux, D3.js, SVG, Kanban, NPM, UI Design, Web UI Design, User Experience (UX), Responsive Web Design (RWD), Responsive Layout, Documentation, Technical Documentation, Tailwind CSS, SQLAlchemy, Google Sites, Styled-components, Figma
  • Front-end Web Developer

    2015 - 2017
    TLT Media Lab, Stony Brook University
    • Designed and developed web-based education software systems for faculty and staff with feedback from stakeholders.
    • Created web-based games for researchers to use in studies with student volunteers.
    • Helped improve lab operations by introducing version control (Git), Kanban boards, and modern JavaScript tooling.
    • Introduced React and helped several team members learn it. Also taught Redux and other related libraries.
    Technologies: JavaScript, SVG, React, Redux, Firebase, jQuery, Git, Trello, Webpack, Kanban, Unit Testing, Front-end, GitHub, REST, APIs, REST APIs, Software, Software Engineering, JSX, Bash, Bash Script, Shell, Shell Scripting, Linux, Python, Lodash, HTML5, React Router, React DnD, 2D Games, Web Development, Heroku, Responsive Design, Adobe Illustrator, Vector Graphics, Image Processing, Python 3, Front-end Development, Dynamic Websites, Web App Design, Web, GUI, Web Pages, Responsive UI, User Interface (UI), Web UI, Web UX, Web App UX, Web App UI, Single-page Applications (SPA), HTML DOM, React Redux, NPM, UI Design, Web UI Design, User Experience (UX), Google Web Designer
  • Web Development Intern

    2016 - 2016
    • Began a project to rewrite the radio station’s website and playlist system from scratch, providing a CMS for admins and DJs to use.
    • Worked on both the front-end templates and back-end Node.js code.
    • Created a CMS with KeystoneJS and MongoDB for radio DJs to add program playlists.
    Technologies: JavaScript, Pug, KeystoneJS, MongoDB, HTML, HTML5, JavaScript 5, Gulp, NPM, Bower, Express.js, Git, GitHub, Mocha, Full-stack, Web Development, Databases, MERN Stack, Responsive Design, Front-end Development, Dynamic Websites, Web, GUI, Back-end, Web Pages, Responsive UI, Web UI, DigitalOcean, Node.js, HTML DOM, UI Design, Web UI Design
  • Android Developer

    2010 - 2014
    • Published a fairly successful app for video editing built on FFmpeg and Android NDK.
    • Implemented dependency injection and created testable modules using Google Guice and RoboGuice.
    • Moved into cross-platform development; picked up React Native, beginning a seven-year love affair with React.
    Technologies: Android, Java, Android SDK, Android NDK, SQLite, RoboGuice, Guice, Google Guice, Dependency Injection, Git, Software, Software Engineering, AdMob, Google AdMob, Google Play API, Google Play Store, GitHub, Relational Databases, Relational Database Design, Mobile UX, Mobile UI, Mobile, Apps, Databases, GUI, App UI, App UX, UI Design, User Experience (UX)


  • Statistipedia Explore

    A web-based data visualization dashboard. It presents the data in a number of plot types like bubble, line, bar, and map and slices the data by different combinations of features. The app's UI is focused on being as simple and minimal as possible, providing sensible defaults and avoiding overload.

  • Personal Website

    A React-based homepage with a unique design. On the desktop, it resembles a macOS interface; on mobile, it resembles a mobile app UI. Two custom React libraries were developed and published as open source—one built on top of React Router to handle nested history (used by the different windows and tabbed navigation) and one for creating custom audio players built with higher-order components used in the player for my created music.

  • NYC Real Estate

    An interactive web-based data visualization of New York City real estate prices using D3.js. Includes linking and brushing features created with DC.js and Crossfilter.

    The dataset was created using Python, Pandas, Numpy, and Scikit-learn.


  • Languages

    HTML, CSS, JavaScript, Python, TypeScript, HTML5, Python 3, Java, SQL, Kotlin, Sass, Bash, Bash Script, Pug, JavaScript 5, Clojure
  • Frameworks

    Redux, Jinja, Django, MUI (Material UI), Express.js, Flask, Next.js, Android SDK, GeoDjango, Guice, Google Guice, Bootstrap, ClojureScript, Jest, Tailwind CSS, React Native
  • Libraries/APIs

    React, Node.js, React Router, React Redux, D3.js, Lodash, jQuery, REST APIs, Pandas, NumPy, Ramda, History API, FFmpeg, React DnD, RoboGuice, Google Play API, Scikit-learn, React Motion, PIL, PiLLoW, Django ORM, Chart.js, React Final Form, SQLAlchemy
  • Tools

    JSX, Redux Thunk, Git, Trello, Webpack, GitHub, GitHub Pages, Mongoose, Android NDK, Shell, Gulp, NPM, Bower, Mocha, Adobe Illustrator, Google Web Designer, Figma
  • Paradigms

    HTML DOM, REST, Web App Design, Web UI Design, Responsive Web Design (RWD), Responsive Layout, Kanban, Unit Testing, Functional Programming, Dependency Injection, Search Engine Optimization (SEO), UI Design
  • Platforms

    Web, Visual Studio Code, Linux, Android, Docker, Firebase, Mobile, KeystoneJS, Netlify, Raspberry Pi, Heroku, Google Cloud Platform (GCP), DigitalOcean, Amazon Web Services (AWS), Google Sites
  • Other

    Front-end, Web Development, Front-end Development, Dynamic Websites, Web Pages, Responsive UI, Single-page Applications (SPA), SVG, Full-stack, Digital Audio Workstations (DAW), APIs, Software, Software Engineering, MERN Stack, Storybook, Responsive Design, Back-end, Multimedia, Documentation, Technical Documentation, Styled-components, Visx, GeoPandas, TopoJSON, Higher Order Components, Maps, Geospatial Data, Data Visualization, Relational Database Design, Music, AdMob, Google AdMob, Google Play Store, Mobile UX, Mobile UI, Apps, Gatsby, Bootstrap 4, Shell Scripting, GeoJSON, 2D Games, Vercel, Vector Graphics, Digital Art, Image Processing, Minimum Viable Product (MVP), Startups, Web Scraping, Video Editing, User Interface (UI), App UI, App UX, Web UI, Web UX, Web App UX, Web App UI, User Experience (UX)
  • Storage

    PostgreSQL, MongoDB, Databases, PostGIS, SQLite, Relational Databases, MySQL, Google Cloud

To view more profiles

Join Toptal
Share it with others