Scientific user communities are widely using computing and storage resources provided by large grid infrastructures. More and more capacity is provided by these infrastructures in a form of cloud resources. Cloud resources are much more flexible for usage but provide completely different access interfaces. Furthermore, grid infrastructure users are often getting access to extra computing resources like HPC centers, home lab clusters, etc. These resources are not part of any formal infrastructure and do not have uniform access mechanisms. Therefore, providing access to all these resources in a transparent way with a unique interface becomes a serious issue. In this contribution we describe the way in which the DIRAC Interware solution can be used to address this issue. The solution will be illustrated by the example usage of the DIRAC4EGI and FG-DIRAC services provided by the EGI and France-Grilles grid infrastructure projects.