A client for a web app that doesn't really exist yet.
PetProject-m68k requires Retro68 to compile.
It will probably require System 7 or later. It may or may not support resolutions under 640 by 480, so I'd suggest using a computer with at least a 640 by 480 resolution display until I know for sure.
If you want to emulate it, use BasiliskII or the Macintosh II version of MiniVMac.