How to animate in new items added to list in ember template

I have a template like this:

<messages>
  
    <message class="">
      
    </message>
  
</messages>

I need to animate additional messages coming in.

Liquid-fire is waiting for someone to implement liquid-each (http://ift.tt/2cS2C3i )

I'm guessing I could use liquid-spacer for the messages container, but that's not exactly my core issue.

Maybe I would animate from my message input box to the message list?

Facebook messenger would be a good example of what I'm after.