hvpp is a lightweight Intel x64/VT-x hypervisor written in C++ focused primarily on virtualization of already running operating system. Although several open-source research hypervisors aimed at simplicity already exist, in my opinion this field is still somewhat unexplored and needs more open-source projects. This can especially help those who have just started exploring virtualization technologies and are looking for small/reference projects. If you're one of them, my bets are that you're really disappointed right now, because all you've got are barely dozen of (great!) projects and huge pile of Intel Manual pages.