anchor.diff:  
   In a first time, we will create a simple Elm application.
   
  -Create a `Main.elm` file inside the folder `packages/elm-app/app/src` with this content:
  +Create a *Main.elm* file inside the folder *packages/elm-app/app/src* with this content:
   
   ```elm
   module Main exposing(main)
  
positive.code: === Checkpoint
  
  Let's check if everything is OK before starting with Elm.
  Start your `meteor` server: 
  ```shell
  # under meteor-elm-app
  meteor
  
negative.code: 4 directories, 7 files
  ```
  
  We will update the *package.json* file to define the main modules in our Meteor app:
  
  ```json
  "meteor": {
  