Awesome

Elm Format on Save

Run elm-format whenever you save an Elm file.

And add the keyboard shortcut Ctrl+K Ctrl+F (or Cmd+K Cmd+F on Mac) to run elm-format any time you want. No need to save.

Install

Install elm-format
Install Elm Syntax Highlighting for Sublime Text
Press Ctrl+Shift+P (or Cmd+Shift+P on Mac) to open the Command Palette
Select Package Control: Install Package
Select Elm Format on Save

Try saving an Elm file to see if it works. You may see a panel open with troubleshooting advice if something has gone wrong!

Including/Excluding Files

Do you only want elm-format to run on certain files? (e.g. only work code)

Go to Sublime Text -> Preferences -> Package Settings -> Elm Format on Save -> Settings

You will see two panels. The left is all the defaults and the right is your custom overrides. So in the right panel, you can override the default settings with something like:

{
    "on_save": {
        "including": ["my/company/"],
        "excluding": ["src/generated/"]
    }
}

This would mean that you only run elm-format on code that is in the my/company/ directory, but you skip any files in the src/generated directory.

See the left settings panel for more information about how to include and exclude files!

Technical Details

This plugin works by modifying the code in the editor itself.

So when it runs "on save" it is specifically running before the file is saved to disk.

This is really important if you have some elaborate file watching system set up! Other plugins may format after the file is saved to disk, triggering a second save, and thereby degrading the performance of your file watching system.