Are you talking about Azure Artifacts? Like I said, I'm using Azure Artifacts as a Private NPM repository for proprietary packages. It also providing caching benefits was a pleasant surprise.

For my projects using Artifacts as their NPM repository, they use an .npmrc at the repository top level to only use that feed (and its pass through capability to the public feed), so for those projects it is the same stack from dev through to production. As I said, the one caveat is that if I need to `npm audit` (which is generally a good idea) I currently have to redirect to the main public NPM feed. Other than that it is a solid replacement NPM feed.