Huh. I honestly thought AIX was dead by now. I remember porting something to AIX 20 years ago, it wasn't fun. I guess IBM stuff doesn't die, it just gets more expensive.
I mean... it's Unix. That's like saying "I ported something to Linux 20 years ago, shouldn't it be dead by now?" and also like saying "I ported something to OSX or Solaris, it wasn't fun" because AIX is Unix exactly like OSX or Solaris.
But it's not Unix-like. It's Unix. It's actually Unix, as in UNIX™.
But at any rate, your comment implied it should be dead because it's so old. Which is a silly statement, considering just how old UNIX™/Unix systems actually are.
Actually it was much better experience than HP-UX, where aCC was stuck between K&R and ANSI C, during the time I happened to do heavy UNIX development.
I wouldn't be surprised if there's more i shops using newer software than AIX shops, nowadays. IBM's own ports of things like nginx, node, and Ruby to "AIX" were all to support i.