We propose in this paper, a mechanism for Grid computing frameworks, for specifying environmental requirements that may set and be optimized by deployers. Specified by designers by parameterizing deployment abstractions, the constraints can be dynamically mapped onto the infrastructure. This work is integrated in the ProActive middleware with the concept of technical services. We illustrate this mechanism with a concrete use case: deploying a component-based application with fault-tolerance on an heterogeneous grid provided by the ProActive Peer-to-Peer infrastructure.