I know it takes advantage of some technicalities (end-of-input separators and such), but it's still a remarkably impressive piece of engineering. I put that up there with some really hairy quines (https://github.com/mame/quine-relay), except it can actually be useful!
I'm counting different editions of POSIX-compliant shell languages (e.g. ksh93, zsh, bash, [t]csh) as different, as well as massively different editions of DOS (freeDOS, MSDOS).
Hence the approximating tilde on "~12". Reasonable minds may consider there to be many fewer, or many more, compatible interpreters.
EDIT: There also appear to be multiple compatible JavaScript interpreters--browser V8 (though not Node, oddly--it's detected as generic; I may send a PR sometime), SpiderMonkey, and older IE. I'm no expert on JS runtimes, though, so the differing results I'm observing may be due to something else.
https://github.com/stephane-chazelas/misc-scripts/blob/maste...
I know it takes advantage of some technicalities (end-of-input separators and such), but it's still a remarkably impressive piece of engineering. I put that up there with some really hairy quines (https://github.com/mame/quine-relay), except it can actually be useful!