.firebaserc file read from .env file

Given that I keep my firebase project secrets in the .env file, is it possible to have .firebaserc file read the project id from .env file. So that I don't need to have the project id hardcoded as I do currently:

.firebaserc:

{
  "projects": {
    "default": "project-dev",
    "prod": "project-prod",
    "dev": "project-dev",
  }
}

Solution

No, it is not possible in the way you're expecting.

Consider filing a request for that on GitHub.

Also consider not committing your .firebaserc at all, and instead generate it using a script you write that reads your .env for data you want to use.