Try It on Your Own Server
Rename the to and fill the env vars:.env.local.env

APIAI_TOKEN=
APIAI_SESSION_ID=some_unique_session_id

The first one is an API.ai API key (Please get one by sign up with API.ai), and the second one is a session ID, which is an arbitrary string (we could make this unique within the app, but that's beyond the scope of this demo).
Or use this Heroku button to deploy to Heroku server. You just need to fill out the env vars with the API key and a session ID. No need to create an file..env