Lars Karbo, Web Development Developer in Oslo, Norway
Lars Karbo

Web Development Developer in Oslo, Norway

Member since December 18, 2020
Lars is an entrepreneur and full-stack developer with eight years of experience. Having been in the early stages of two startups, he knows how to rapidly develop an MVP and bring a product to market. As an open-source library maintainer, he writes clean and maintainable code that's efficient and production-ready. His experience in marketing and communication has given him a big-picture view of what businesses actually need. This helps him make informed, quality decisions in the tech landscape.
Lars is now available for hire


  • Self-employed
    Google SEO, Spotify API, Tailwind CSS, Serverless, Stripe, Growth Marketing...
  • GrowthDay
    React Native, TypeScript, Jira
  • Drowzee
    Neuroscience, React Native, React, JavaScript



Oslo, Norway



Preferred Environment

MacOS, VS Code

The most amazing...

...thing I've made is Napchart, a full-stack visual time planner web app. It's used by thousands of polyphasic sleepers and has 120,000 saved documents.


  • Founder | Web Developer

    2020 - PRESENT
    • Started a project called Making 12 Startups in 12 Months in November 2020 to challenge and improve my ability to build and ship work that matters.
    • Prepared a successful launch of on Twitter, Reddit, and ProductHunt, bringing over 2,500 visitors.
    • Released in one month. is a React app that lets you organize and annotate samples from Spotify and YouTube APIs.
    • Gained over 300,000 views on TikTok after sharing my entrepreneurial journey. Using social media in this way can be uncomfortable but yields great results.
    • Released in one month. FileParty is a high-quality screen-sharing alternative that transfers media files in real time between browser instances, using WebRTC for direct P2P file transfer.
    • Built and developed, a crypto NFT market analysis tool.
    • Founded Personate AI, a tool that lets you create personalized human avatars for any business need.
    Technologies: Google SEO, Spotify API, Tailwind CSS, Serverless, Stripe, Growth Marketing, Gatsby, Firebase, Netlify, React, JavaScript, Crypto, Non-fungible Tokens (NFT)
  • Full-stack Developer

    2021 - 2021
    • Developed a React-Native application for iOS and Android together with a team of four developers.
    • Launched the app through the alpha, beta, and public phases. Used TestFlight to gradually let people test the app.
    • Converted the legacy JavaScript codebase into performant and type-safe TypeScript code.
    Technologies: React Native, TypeScript, Jira
  • Tech Lead

    2019 - 2020
    • Developed a React Native app with signal processing capabilities that transformed brain waves into sound.
    • Secured the app for passing high privacy standards needed for medical certification.
    • Trained three engineers to be proficient in React Native.
    • Made and deployed infrastructure on DigitalOcean for storing sensitive EEG data averaging over 300,000 data points per session.
    • Negotiated and chose the best hardware EEG supplier based on delay, signal quality, jitter, and connection API.
    Technologies: Neuroscience, React Native, React, JavaScript
  • Full-stack Developer

    2018 - 2018
    SecondBrain, Inc.
    • Developed a React Native app that interfaced with an API to a Python machine learning back end.
    • Made a successful real-time text collaboration system.
    • Went through the Techstars Los Angeles accelerator, learning a lot on the startup journey.
    Technologies: React Native, JavaScript
  • Web Developer

    2016 - 2017
    • Developed client websites for local businesses in Norway.
    • Created an internal reusable CMS for use across different projects.
    • Managed client processes and learned how to work efficiently with clients.
    • Created a custom tour booking system using Stripe.
    Technologies: CSS, JavaScript, Web, Node.js
  • Founder | Web Developer

    2013 - 2016
    • Developed a time visualization web app daily used by hundreds of users with over 120,000 charts saved.
    • Developed custom graphic rendering in JavaScript using HTML5 Canvas.
    • Communicated and worked with the users and community to set the direction for the project.
    • Added advanced animations and tweening functions to the visualization.
    Technologies: Firebase Cloud Functions, Firebase, SVG, Redux, React, Animation, Visualization, HTML5 Canvas, JavaScript
  • Founder | Web Developer

    2010 - 2013
    The Fake Virus
    • Developed a website and CMS for a website where users could download computer pranks.
    • Implemented Google AdSense and earned some revenue from the ads.
    • Optimized 50+ listings for SEO and monitored them with SEO tools.
    Technologies: PHP, JavaScript


  • 12 Startups in 12 Months

    A project I started in November 2020, where I launch a monetizable project every month for a year. This is an effective way to learn more about marketing, launching, and monetizing, aspects that are just as important as the technical part.

    Most of the projects will be built as web apps. React, Stripe, and Serverless are the technologies I will use on most projects. The key is fast, solid development, and shipping work that matters.

    Doing this individually, but together with five other makers from all over the world in a cohort called 12xStartup.

  • Slapper

    Slapper is a web app that organizes songs and snippets from music services. It also lets you annotate, collaborate, and share your collection.

    The app is written in React and Expo and uses Serverless functions, Netlify and FaunaDB to provide a seamless, modern experience.

  • FileParty

    A web app for real-time file transfer and presentation. Users can sync playback and share files with P2P capabilities written with WebRTC and WebTorrent.

    FileParty is an experimental web app built to explore the possible future uses of modern web APIs like WebRTC. It can be used as a lossless, high-quality screen sharing alternative.

  • Napchart Time Planner

    A visual time planner used for experimenting with polyphasic sleep. The site is a web app built with React and Firebase and hosted on Netlify. The core part of the app is an HTML5 Canvas with custom graphics, interactivity, and animation.

    Napchart is still used as the primary tool for sleep hackers and recently hit 120,000 saved charts.

  • FocusMonkey

    A smart productivity timer that gives you music as a reward. This web app connects to the Spotify API and lets users choose which playlist to play while working and which one to activate after a given amount of time.

    FocusMonkey was launched on Product Hunt in 2020 and is still active.

  • Lars Karbo Blog

    My personal blog, where I craft my thoughts, talk about projects, and share knowledge. It also contains a newsletter that I plan to grow during the years.

    The blog is built with GatsbyJS and made with long-term SEO in mind.

  • Personate AI

    A startup specializing in AI-generated videos of humans. I co-founded this and was responsible for the whole technical architecture. We had some pilot projects with big government organizations in Norway, but haven't yet found our product-market fit.

  • Rude Boy's | NFT Collectible Art Project

    I made the website for Trym Ruud, a Norwegian NFT artist. The Rude Boy's site updates itself based on data from the Ethereum blockchain and OpenSea. Since the launch of the website, the project has grown by more than $1,000,000 in value.

  • TokenBird | NFT Market Watch

    A web app for tracking popular NFT projects. Sources data from the Ethereum blockchain and OpenSea and aggregates the data to useful, human-readable insights. The app was launched on Product Hunt in September.


  • Languages

    JavaScript, CSS, TypeScript, GraphQL, Python, PHP
  • Frameworks

    React Native, Express.js, Tailwind CSS, Redux
  • Libraries/APIs

    React, HTML5 Canvas, Node.js, Product Hunt, Spotify API, WebRTC, YouTube API, Stripe
  • Platforms

    Firebase, Netlify, Twitter, Web, Blockchain, Ethereum
  • Storage

    JSON, Databases
  • Other

    TikTok, Google SEO, Launch Strategy, Web Development, Architecture, Front-end, HTML5 Audio, APIs, Community, Validation, Chrome Extensions, Firebase Cloud Functions, Neuroscience, Animation, Serverless, FaunaDB, Visualization, SVG, Gatsby, Growth Marketing, Writing & Editing, Blogs, SEO Content, P2P, Crypto, Non-fungible Tokens (NFT), Videos
  • Paradigms

    Jamstack, Rapid Prototyping
  • Industry Expertise

    Web Design, Social Media, Marketing
  • Tools

    Expo, Jira

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