Avoid having both proxy and hosted repositories in the same group repository

With the Nexus repository manager, you can group both the proxy repositories and hosted repositories together into a single group repository. It's been found that this will drastically reduce the Maven build performance, as Maven still checks in remote repositories even if the artifact is available in the hosted repository. If you still want to group all repositories, then you need to make sure you have the right setup of inclusive/exclusive rules defined. This was discussed in detail in Chapter 8, Maven Repository Management.