Thanks! I didn’t know that, as I haven’t yet to try out Go 1.11. <grin, duck, run>
For snapcraft.yaml, I am taking the easy way out by setting GO111MODULE within the override-build script, alongside where GOPATH and PATH were set: snapcraft: Set GO111MODULE=on in override-build script · gohugoio/hugo@3ddbb7f · GitHub (testing it on the extended-snap-master first before pushing the change to master and stable branches)
Update: Nope, setting GO111MODULE=on globally didn’t work. Strange errors with other Go packages. I’d better follow your example in .travis.yml by applying env GO111MODULE=on to the go get github.com/magefile/mage command only.
Update 2: Nope, that didn’t work either. That means I really should look at your latest changes to Appveyor YAML and https://github.com/magefile/mage/issues/79 carefully. Haha, not as simple as I had thought!