(Second try. I sent this message last friday, it did not reach the Datetime mailing list).
Last thursday, I have published to CPAN6 version 0.0.2 of Raku module Date::Calendar::MayaAztec. The basic difference is that I have added a "semi-hidden" attribute "daycount" to Aztec dates to store the Modified Julian Day number. As a consequence: Now you can convert *from* the Aztec calendar, in addition of converting *to* the Aztec calendar. When building an Aztec date, you should give a reference date, to generate, for example, the Aztec date "on or after Gregorian date 2020-01-01". This additional build parameter is optional and defaults to "nearest to today's date". Thanks to code sharing, now you can also build a Maya date like you build an Aztec date, that is, by giving the calendar round values (Haab and Tzolkin), plus a reference date. This is in addition to building a Maya date by giving the long count value. https://modules.raku.org/dist/Date::Calendar::MayaAztec:cpan:JFORGET https://github.com/jforget/raku-Date-Calendar-MayaAztec Thank you for your interest in Raku and in foreign calendars. Jean Forget JFORGET at cpan dot org
