Right now the Citoid extension relies on Citoid being behind restbase, and uses the url gotten from the VE config. However, it would also be helpful to expose a restbase url to the config for future use, such as Wikidata config. (i.e. on mw.config on wikidata right now, wgCitoidConfig = {
citoidServiceUrl :"https://citoid.wikimedia.org/api"} which is a deprecated url.

The other use case is people wanting to use citoid's public API on their own wiki, see: https://www.mediawiki.org/wiki/Topic:Ugk074v207yxgao8