Whenever you deploy your application on Viaduct, we do a number of checks to make sure that your processes have started and are running properly before make the deployment active and send public traffic to your processes.
This is a great way to ensure that you don't accidentally push broken code into production however it can be a bit of a pain when you're first deploying an application and need to do some debugging to see what additional configuration you may need to add.
You can now choose the Force Start option when creating a new deployment. When checked, Viaduct will not check that processes start successfully and will go ahead and make the deployment active straight away. This will then allow you to use the console of the broken deployment to debug your live environment.
You can also specify the force_start parameter when you start a deployment from the start deployment API.