@tekin I think https://github.com/alphagov/whitehall/commit/db1d2ed65a6f905d9000d230910e1a3292f7e314 is better because I am only overriding GOVUK_APP_DOMAIN if it is already set and I am now expecting GOVUK_APP_DOMAIN in the output, rather than hard-coding a particular domain. Does that seem like the right thing to do here?