PlantUML also has gantt chart (https://plantuml.com/gantt-diagram ) support. unfortunately does not scale below days. There is a chronology diagram(https://plantuml.com/chronology-diagram) available but not linked from the main documentation or documented very much at all. Though it looks like the correct diagram in plantuml for the data in OP is a timing diagram (https://plantuml.com/timing-diagram)

perl + Template Toolkit (using the underdocumented support for the fragment pattern with EXPOSE_BLOCKS), before finding htmx we used Jemplate, which let you compile Template Toolkit templates into Javascript functions

Contrary to what seems to be the rough consensus here, ESB/SOA (+ SOAP + WSDL + XML + ...) the 'correct way to do microservices' is probably something more like Self-Contained Sytems (SCS)

https://scs-architecture.org/

Probably worth noting is that elvis is the origin of nvi (New vi) which is the default on the BSDs

posix vi, ovi and nvi lack an X command

there is no else unless (or even elsunless, since this isn't javascript) in Perl, might have been

    unless (predicate) {
       do_this;
    } else {
       do_the_impossible unless impossible_thing;
    }

Thanks! Added!

s/every language/some languages/

contrary to pikchr documentation, troff is not obsolete

No technology popular enough to attract an audience ever goes away. However, would you care to speculate on how many troff documents were written in 2021 versus Markdown docs?