@xconde @Meyerweb somewhere I probably still have a copy of the pre-compiler sendmail.cf I made to do least-cost name-, host-, and transport-based routing.
i may even also have the tools I wrote to manage it, which was... kind of like a sendmail compiler before there were sendmail compilers. xD
sendmail is terrifying and hilarious and i still run it out of spite
@moira maybe it's because I never learnt how m4 macros work, but I think people like you are wizards.