We would be able to have a "**{icon fighter-jet} Land**" button in {R4}.
For security reasons this requires separated SSH credentials, so another Drydock Blueprint host, in order to separate the building stuff to the landing stuff.
Why? Because the building stuff should be considered very untrusted and dangerous and should never be able to interact with the landing stuff that should be kept without untristed contamination.
As already said this can be achieved with two SSH users on the same host because the default `umask` is good to avoid that one SSH user could be able to write from the other.
Upstream guide:
https://secure.phabricator.com/book/phabricator/article/drydock_repository_automation/
WikiBooks Guide:
https://en.wikibooks.org/wiki/Phabricator_Administrator%27s_Handbook/Continuous_integration#Setup_1:_on_own_hardware_(using_Drydock)