I was a little reluctant to flip things over to purescript-json as it's not had heavy usage yet, but realistically it's mostly the same as argonaut-core anyway, so yeah I think pointing people there is fine.

The main thing would be that there is no traversals or codecs equivalent for it. I don't think traversals got much use, codecs definitely does, but I have no interest in creating/maintaining a typeclass codecs library equivalent. I know some people will not love that, since it's undoubtedly more convenient than the value codecs approach I prefer (until it isn't 😄), but I suppose there's yoga-json for something more along the lines of that approach (mostly, it's more intended for convenient usage of JSON equivalent PS types so still might need a layer of serialization types).

This looks good to me, I think we should merge?

I retract this. I'm in no hurry to deprecate this package. I have no opinion.