A virtual conference platform for academic conferences, built by academic conference organizers.

Organizing social interaction at virtual conferences shouldn't be like herding cats

CLOWDR is an open source tool suite to make it easier to run interactive and engaging virtual conferences. Imagine that your conference attendees could video and text chat with each other and easily drift between different conversations in different rooms. Now imagine that this app also integrated your conference program (directly imported from, and let attendees see who else is watching the same content. We were unable to find a technology platform that allowed for these interactions, so we built CLOWDR.

CLOWDR is a community-driven effort to create a new platform to support Conferences Located Online by using Digital Resources. CLOWDR lets your virtual conference attendees still be "present" in the virtual conference by engaging with each other through text and video chat directly integrated with your conference program. However: we don't sell CLOWDR as a service - it is an open source project that is designed to be easy to deploy and scale: it runs entirely in the cloud.

As conference organizers ourselves, we recognize that no conference organizer wants to pay an arm-and-a-leg for services like this, but also that no conference organizer wants to take on running their own (cheaper) streaming video platforms. Real-time text and video chat are the most infrastructure-intensive services to run; we outsource this to Zoom (for large presentations) and Twilio (for all ad-hoc calls). We have found this approach to be extremely cost effective: conferences pay only for the number of Zoom licenses that are needed to support concurrent live streaming sessions, and then all breakout sessions and text chat run through Twilio, who bills only for actual usage (by the minute) --- ICSE's entire Twilio bill was under $250.

If you are interested in using Clowdr for your event, there is no need for you to download any code or run your own server (unless you want to!). We can host your backend server for free, the only costs to your conference are for streaming video (you'll need accounts with Zoom and Twilio). CLOWDR has been battle-tested by thousands of users already this year at PLDI, ICSE and ISSTA. In August, VL/HCC and ICFP plan to use CLOWDR. As we gain deployment experience, we hope to offer conference organizers a one-click installation of CLOWDR. However, in the meantime, if you are considering CLOWDR for your virtual conference, please email us at [email protected] and we can provide a demo and deployment for your conference. We also have a User's guide for interacting with CLOWDR, and an Operator's guide for deploying CLOWDR that answer many frequently asked questions.

Let's make the best of this situation, and put our heads together to make the best virtual conference experience that we can: together.

CLOWDR is created by Jonathan Bell, Crista Lopes and Benjamin Pierce.

CLOWDR is made possible thanks to support by the National Science Foundation under awards CCF-2035003, CCF-2035101 and CCF-203500 and support from