By default, we automatically alias the default branch (usually master) if there is an alias field in the now.json file.
To disable aliasing automatically, use the github.autoAlias option in your now.json configuration:
If the Now + GitHub app has been installed and there is a now.json file in an enabled repository, we will start building the app for every git push.
Note that since each push to Now is assigned a unique deployment URL, these deployments will not affect your production URL unless you have an alias setup and have not disabled auto-aliasing or even Now + GitHub entirely.
Sometimes deploying with Now + GitHub can cause unexpected behavior. One such case is when your app is a background worker, and it starts accepting tasks or jobs even though you did not alias it to production.
In such a case as a background worker, you might want to stop Now + GitHub support for that repository completely. To do that, add the following option to your now.json file.
This configuration represents a now.json file with Now + GitHub disabled.