Today's off-the-shell virtualization solution is ridden with complexity. Application of virtualization call for trustworthy solutions. Complexity defeats trust. Microkernels with virtualization extensions and user-level VMMs on top are a approach to mitigate complexity. Modern microkernels like seL4, the NOVA microhypervisor, Genode's -hw- kernel or Fiasco.OC are such promising candidates. Fortunately and unfortunately, the diversity come with fragmentation of the small microkernel community. There are several VMMs for each platform tight to a specific microkernel, rendering it unusable across various kernels. Genode supports several kernels already, so that unification of virtualization interfaces for VMMs across kernels seem to come into reach. Does it ? The talk will cover the venture and current state of harmonization hardware-assisted virtualization interfaces to fit into the Genode OS framework.