That's correct. The expectation is that you set up the dependencies you need in a sequence of zero or more sequential go get commands, and then you can concurrently invoke go build, go test, and so on as much as you like.

There isn't a good way for commands like go get to incorporate concurrent changes without starting over completely, and we don't want to keep the files locked for an arbitrarily long time while go get is working — that would just result in the same kind of sequential operation that you can already do by leaving off the &.