  While they have long been a subject of academic study, social virtual reality
(SVR) systems are now attracting increasingly large audiences on current
consumer virtual reality systems. The design space of SVR systems is very
large, and relatively little is known about how these systems should be
constructed in order to be usable and efficient. In this paper we present Ubiq,
a toolkit that focuses on facilitating the construction of SVR systems. We
argue for the design strategy of Ubiq and its scope. Ubiq is built on the Unity
platform. It provides core functionality of many SVR systems such as connection
management, voice, avatars, etc. However, its design remains easy to extend. We
demonstrate examples built on Ubiq and how it has been successfully used in
classroom teaching. Ubiq is open source (Apache License) and thus enables
several use cases that commercial systems cannot.
