Cannot use env values in serve references

[chengyak]

I have settings:

serve:
  port: {env.service_port}
  playground: {env.playground}

But it didn't load the values from my .env file, is this not supported?

Also, it looks like if I modify the settings such as port, playgound after mesh build, mesh start will still use the old values. One of the man use case for us is for production, we want to disable the playground, but looks like after the mesh build, I cannot modify that setting for different env anymore.

what is the best way to achieve something like the NODE_ENV in Apollo Server (https://www.apollographql.com/docs/apollo-server/v2/testing/graphql-playground/)
Please advise, thanks