Circulation log not returning any results on Nolana Bugfest

The circulation log app is not returning any search results.

When you put in a query that should return results, nothing appears.

Looking in Chrome Developer Tools, it looks like any query that is sent by the app UI returns a response of

{ "message" : "Failed to resolve '$DB_HOST_READER' after 2 queries ", "code" : "HTTP_BAD_REQUEST", "parameters" : [ ] }