Sometimes the app boots slowly on Heroku instances and fails to fully start within 60 seconds with results in a failed launch. Just watch out for this and retry if it happens. We are looking at ways to address this.
Heroku’s 30 second timeouts on all web requests can cause a few issues if you happen to have longer running database queries. Most people don’t run into this but be aware that it’s possible.
If you don’t access the application for a while Heroku will sleep your Metabase environment. This won’t harm anything, but it can seem like the application is slow to respond when actually it’s just Heroku waking up the environment.
For more information about running on Heroku check out our documentation