The fundamental problem of dependency management, as anyone who ever kept bookmarks knows, is that the external sources might go away at any time. It's not a pr

The fundamental problem of dependency management, as anyone who ever kept bookmarks knows, is that the external sources might go away at any time. It's not a problem unique to Deno or Go. Take Java for example, its standard dependency management tool is Maven, which relies on external repositories of artefacts to function. From time to time, a repository might go down, or it might be moved to another address, or a library might be migrated to another repository. Whenever this happens, your build might break. The solution is to proxy all requests at the organizational level through your own server which keeps a mirror of any package that has been referenced once. That way, if it become unavailable externally, then you can still use it internally. You can also override packages with patched versions if they misbehave. I think that Deno should define a standard dependency fetching protocol, and allow proxying transparently at a native level. If it does, that kind of dependency management will be fine.