Frontity with wpengine


After finishing the tutorial, I tried changing the URL in frontity.settings to my wordpress site. Using a URL for a vanilla wp site works: But when I use a URL for a wp site hosted in wpengine,, I get an error.

The browser displays: invalid json response body at Daniel Reznick Site – Your SUPER-powered WP Engine Site reason: Unexpected token < in JSON at position 0

What is the correct way to use Frontity with wpengine?