Metadata is nice when the data shape that some function/library needs is almost perfect. Than I can smack on what I need as metadata and I don't need to invent some data structure of my own and transform it for the said library/function. Example, I found the reitit routing tables to be exactly what I want, except I want to add the HTML title for each route and use it differently on the client and the server. Metadata to the rescue. 😃
I also like to tuck in unit tests together with my functions. Like I describe here: https://clojureverse.org/t/inline-tests-do-you-do-it/4083
(Granted, there it is the defn
macro that gives me an alternative way to provide the metadata, but anyway.)