How are environment variables loaded from "config.yaml" in a development environment?

[PaulRBerg]

From the docs on fallback RPCs, it appears to be possible to use environment variables in the config.yaml file. I've added mine like this:

name: Greeter
description: Greeter indexer
networks:
  - id: 1
     rpc: https://mainnet.infura.io/v3/{ENVIO_INFURA_API_KEY}

But it's not clear to me where should I put the environment variables when running envio dev. In an .env file? If yes, where should the .env file be located? At the same level with config.yaml?

I couldn't find any information about this in the docs.

[DZakh]

It's either .env at the project root, or you can set the variables via UI on the Hosted Service.

[PaulRBerg]

Thank you.

enviodev/docs#651