Hey
This is a series of posts that I will be maintaining on the forum. Each one will focus on a specific distribution and release (as appropriate). Each one will be backed by automatic tests that can replicate that experience.
On Debian 9 (stretch) today we have a bug where apt-get install snapd followed by snap install hello-world breaks while snap install core; snap install hello-world works correctly. I will be addressing this issue soon, linking to pull requests and bugs.