Specify Registry via Environment Variable

[darelius-b]

Is it possible to specify a registry URL via environment variable? Something like:

"registries": [
    {
      "kind": "git",
      "repository": "${REGISTRY}",
      "baseline": "abc123",
      "packages": [...]
    }
  ]

In our dev env, we have two repositories. One contains customer proprietary information that only a select handful of devs are allowed to access whereas the other is open to all with fake data. For vcpkg, we'd like to have just one manifest, but allow the devs to decide which version to pull based on environment.

Is this possible? If not, any suggestions on other ways to accomplish this with vcpkg?