Failed to launch: determine start command: when there is no default process a command is required

Hey @Grant_Magdanz,

It seems you have a Dockerfile in your project, is there any reason not using it and using buildpacks instead?

We have regularly issues with Buildpacks as we heavily depends on Heroku images. We recommend using Docker for production / anything serious and Buildpacks for quick tests eventually.
Is there a way for you to use Docker instead?

Thanks