Error 503 hostname doesn’t match against certificate. Looks like some work is being done. Could also be the host cache server is hosed.

Duplicate of this thread: Julialang.org website unreachable?

(docs.)julialang.org is down

Topic		Replies	Views
Julialang.org website unreachable? Offtopic	5	1241	July 14, 2017
Certificate error on julialang.org Meta Discussion	2	746	July 17, 2017
New Julialang.org Website Repo and Test Url (https://julialang.io) Community	13	922	January 2, 2020
Couldn't reach Julia Chinese community for couple of days Community	1	528	December 21, 2021
Docs.julialang.org in Chrome cert revoked General Usage documentation	2	470	August 5, 2020