HTTP GET /nodes fails

The HTTP API is failing me. /flows works fine, so doesn't seem to be a permissions issue. /nodes returns nothing. Opening the browser console shows the following errors

Uncaught ReferenceError: RED is not defined
at VM331 nodes:160

Uncaught TypeError: Cannot read property 'registerType' of undefined
at VM333 nodes:603
at VM333 nodes:885

Then a couple dozen more registerType undefined errors.

What gives?