Basically it should be possible for the owner of a tank to declare that when a tiddler is saved in that tank the JSON of the tiddler (maybe skinny) is POSTed to configured URIs.

All tiddlers are already being sent down the tiddlywebplugins.dispatcher channel but only tiddlers which are readable by GUEST go down the tiddlywebplugins.jsondispatcher channel.

A listener of some kind would do the POST.

A question is when to store the hooks. User associated hooks could be stored in _<username>-data bag but since we want tank associated hooks they would need to be in the tank. A _webhook tiddler@docs perhaps?

That fits in with the TiddlyWiki history of active stuff being right there in the mix.