Tailorable technologies are technologies that are modified by users in the context of their use and are around us as desktop operating systems, web portals, and mobile telephones. While tailorable technologies provide users with limitless ways to modify the technology, as designers and researchers we have little understanding of how this should affect design. In this paper we present principles from four designers to strengthen inquiry into tailorable technologies. We then apply the principles to the case of the design of a web portal. We conclude that designers need to more consciously build reflective and active design environments and gradients of interactive capabilities in order for technology to be readily modified in the context of its use.