This paper describes our experience using a functional language, Haskell, to build an embedded, domain-speciﬁc language (DSL) for component conﬁguration in large-scale, real-time, embedded systems. Prior to the introduction of the DSL, engineers would describe the steps needed to conﬁgure a particular system in a hand-written XML document. In this paper, we outline the application domain, give a brief overview of the DSL that we developed, and provide concrete data to demonstrate its effectiveness. In particular, we show that the DSL has several signiﬁcant beneﬁts over the original, XML-based approach including reduced code size, increased modularity and scalability, and detection and prevention of common defects. For example, using the DSL, we were able to produce clear and intuitive descriptions of component conﬁgurations that were sometimes less than 1/30 of the size of the original XML.