Contexts spawn a goroutine to block on the Done channel. You always need to call cancel otherwise you'll leak that goroutine. It's an annoying thing that comes

Contexts spawn a goroutine to block on the Done channel. You always need to call cancel otherwise you'll leak that goroutine. It's an annoying thing that comes from the fact that contexts are implemented in user space and there's no way to block on a channel without block a goroutine.