Tarmac64 is an Open Sourced C# tool for editing the Mario Kart 64 USA .Z64 format ROM image. It is a contribution of knowledge from multiple people. There are two product versions, both free and open sourced. The main build is the Tarmac64 Developer Version, which features the full toolset including several debugging and untested toolsets. The build intended for release and distribution is the Tarmac64 Designer Version. Both versions are intended to be used and distributed freely without restriction, but the Developer Version is not officially built or supported.