Jambi is a PE infector that will prepend a shellcode to a binary, thus preloading the shellcode. At the execution stage, both shellcode and binary will be run simultaneously.
The compiler used is x86_64-w64-mingw32-gcc (That is, migw32 with TARGET=HOST=amd64). Edit it to suits your needs.
Due to Cygwin specificities, running the infected binary can sometimes fail on Cygwin. If repeating the process 3 or 4 times always result in s failure, try cmd.exe.