  In this paper, we present how we created a Domain Specific Language (DSL)
dedicated to IP Multimedia Subsystem (IMS) at Ericsson. First, we introduce IMS
and how developers are burdened by its complexity when integrating it in their
application. Then we describe the principles we followed to create our new IMS
DSL from its core in the Scala language to its syntax. We then present how we
integrated it in two existing projects and show how it can save time for
developers and how readable the syntax of the IMS DSL is.
