An alternative to all this would be to build it manually using:
go get -v -x github.com/lxc/lxd/lxc
go get -v -x github.com/lxc/lxd/lxd
But that won’t get you the init scripts and distro integration bits that are usually quite useful. Also you’d need to manually update and rebuild all of it every time we change something.
@zhenech looks active in the ITP but it’s too late for Debian 9 as it’s already in full freeze. So for Debian 9 the snap is more likely to work out of the box (once the snapd guys have fixed that bug) and hopefully once LXD makes it to unstable, someone can backport it so that Debian 9 users can use it.