To setup a basic Dune installation via Homebrew activate first the external repository bempp/homebrew-bempp via

brew tap bempp/homebrew-bempp

The available packages are dune-common, dune-geometry, dune-localfunctions, dune-grid and dune-alugrid. For example, to obtain a basic installation of DUNE together with Alugrid just use

brew install dune-alugrid

All dependencies of dune-alugrid are pulled in automatically. This was successfully tested on Mac OS 10.10.3 with Xcode 6.3 and a fresh installation of Homebrew.