Just as an FYI - https://docs.snapcraft.io/467 references the first post of this thread:
Set snapd proxy via core configuration
One topic that came up during the sprint is that there is no easy way to set the proxy for snapd. On a classic system this is easy via editing /etc/environment. However on an ubuntu-core system this file is read-only. Providing an easy way to set the proxy on core this way would be beneficial.
Perhaps rework the content or remove this thread from the docs build?