I tried to make a quick example with it and failed.

I kinda knew it would -- reinventing a compiler is hard -- it much simpler to compile a c program to dump the structure of struct, kinda sorta the trick C::DynaLib::Struct/hparse employs

I suppose you could always "fingerprint an os" and build a database of time formats ... pure-perl is pure insanity if you ask me, much less work to install a compiler :)