 Hi, we are Chatmospher, I'm David and I'm Anke and we're very happy that we are invited to talk about our little project. Chatmospher is a video chat programme and it was created during the first lockdown in Germany when in early 2020 we were not allowed to meet our friends anymore and we tried a lot of digital video chat tools to meet and we realised that Zoom and Jitzi and Teams, Google Hangouts, they all have this logic of work tools where one person can talk at a time if multiple people are talking then sound is changed so that you can hear one person better. More introverted people don't feel as comfortable in joining a conversation or they started not to come anymore and we wanted to create this dynamic as if we would sit on a real table where you can talk to one person but you can also talk to someone else or you can just listen or maybe just have a side conversation. So with this idea we applied to the Prototype Fund which is a German tech fund supporting open source civic tech and in this round we had the opportunity to try if we could find actually a better paradigm. So I wanted to share a way how we were working. We did a design sprint very quickly so we tried to figure out what we want to do before even write one single line of code and this is something that we can really recommend because you learn a lot from just putting your stuff in front of a real user because we had this idea that we want to have 3D sound that would be somewhere in space and so I can hear that somebody might be here next to me and it could change all the time. When we tested we only had a mono output signal because we just had one box to test with. We can see it in the picture behind the screen but the interesting thing was it worked. People just realized that changing the loudness or the volume based on proximity made the effect as if you would move through this room. So we realized very quickly that it could work easier and from there on we started creating it. How it's built is it's based on JITZI. JITZI is an open source video chat app. I assume most of you know it if not definitely check it out. It's awesome. So chat atmosphere is open source of course. It's a React app that is utilizing Zustand as a state management tool as a replacement for Redux. Also a quick shout out to them. It's also awesome. You should check it out. Like Anke said what we are doing is we calculate the distance of the users and by this we vary the volume. This is something that we came up with and we send out the user's position via messaging. Everything else is basically utilizing core JITZI functionality that we adjusted to our needs. Currently there are many cool ideas and a couple of forks out there what to do with this setup as a base but to collaborate with you and everyone else who's interested we urgently need unit testing. Since I'm not fluent with writing unit tests especially architecture wise also mocking of WebRTC is something that I'm looking into but I would be very happy to have someone experienced to talk to about it. So maybe one thing to mention just as a side note we also built PlayWave. It's a load testing tool we made to test our architecture to test chat atmosphere but it can also be used to do integration testing and it's using PlayWright which is a headless browser automation tool something like Puppet here. So you can also use it to test all other setups of WebRTC for example JITZI. So you can try it to load test your JITZI install and it's much leaner than Selenium is. So also try that, try chat atmosphere, install it, adjust it to your needs and please get in touch if you want to help out with unit testing we would be very happy. Thanks very much for your attention. Have a great conference. Yes, bye.