I'm Guillaume Besson and I spend a lot of my time coding. I've been working with startups as a freelance fullstack developer for more than 7 years. I help them deliver fast, usable and secure products by focusing on understanding the vision behind the product. I mainly use Javascript with NodeJS and React.

When I'm not working for my clients, I love to build products and open-source projects. I've built:

  • DBacked: database backup as a service for PostgreSQL and MongoDB which creates, encrypts and stores your database backups and alerts you if something's wrong before it's too late
  • Soundsync: Soundsync links all your speakers, old or new, smart or dumb, from the same brand or not, in one easy-to-use interface to enjoy your music in sync anywhere in your home
  • RoundGames: RoundGames is an online multiplayer gaming platform focused on bringing the best experience for small groups (friends, family) but also for huge communities like those of Twitch streamers. Regularly, games with more than 30k+ simultaneous players are hosted on the platform

When I'm not coding, you can find me rock climbing, building drones or cooking some quite good home-made pizzas.

Some of my work

Lead fullstack developer at a video game studio


Built a Twitch extension for the release of a video game that let viewers impact the game experience of the streamer. Used in live sessions with more than 20k viewers. Composed of a Windows program that fetch events from the game, a NodeJS backend hosted on AWS and a streamer front-end in React.

Lead fullstack developer at a company in the vacation rental space


Built a meta search engine to browse all the homes on Airbnb, Booking.com and other comapnies from a single page. Fully integrated the APIs of these providers to normalize in our database all the data of each home. Used Next.JS (React), NodeJS, PostgreSQL deployed on Google Cloud.


Lead fullstack developer at Streamup


In a team of 3 developers, I built a chat system to handle more than 300k simultaneous users with NodeJS and React. Rebuilt the video player with HLS and deployed an in-house CDN in more than 10 countries to serve live video to more than 20 millions monthly active users.