Limit snap to root user only

If you have some users logging to your server, that don't have root access, and you want to limit snap to root user only, you can do the following:

1) Set snap refresh schedule, for example

sudo snap set core refresh.schedule=02:00-03:00

2) Set cron to limit permissions to root users after updates

For example, sudo to root, and edit root cron with nano:

sudo su
export EDITOR=nano
crontab -e

and add there that at 03:10 permissions are limited to root again:

10 3 * * * chmod og-rwx /usr/bin/snap
10 3 * * * chmod -R og-rwx /var/snap

You can see crontab syntax help at https://crontab.guru

snap is the command, and /var/snap is where data is stored.

Future snap features for permissions

For more advanced user permission control in snap, sometime new features will be added:
https://forum.snapcraft.io/t/multiple-users-and-groups-in-snaps/1461/3