In this paper, we advocate an approach to combine formal specification components. Our work aims at building or reusing specification components, and compose them with a gluing language constituted of a minimal but sufficient set of operators. The glue allows to have at one’s disposal a global formal specification with heterogeneous components as basic entities. The interests are manifold: modelling the different aspects of systems, allowing the use of many existing specification languages, formalizing the links between components in an easy and graphical way, making the reuse of components easier. A case study about a vending machine is specified to illustrate how this approach could be practically used.