  Smart Built Environment is an eco-system of `connected' and `smart' Internet
of Things (IoT) devices that are embedded in a built environment. Smart
lighting is an important category of smart IoT devices that has recently
attracted research interest, particularly for residential areas. In this paper,
we present an extended reality based smart lighting design testbed that can
generate design prototypes based on the functionality of the physical
environment. The emphasis is on designing a smart lighting system in a
controlled residential environment, with some evaluation of well-being and
comfort.
