This probably went unnoticed because we don't actually _have_ any Dub-based packages. Anyway, from that log:
> source/dub/internal/vibecompat/data/json.d(2111): Error: template > instance `enforceEx!JSONException` template `enforceEx` is not > defined, did you mean enforce(E : Throwable = Exception) if > (is(typeof(new E("", string.init, size_t.init)) : Throwable) || > is(typeof(new E(string.init, size_t.init)) : Throwable))? Something something templates, something something throwable, something something optional type, something something second-system syndrome. Seems likely to me that our Dub is too old for our ldmd2. I'll send a patch to update it.