Meltano

I've now correctly installed the custom tap. Looking good! I worked through the settings and the config UI in meltano. My situation is dealing with a data source that is a multi-tenant API. I've dealt with this by dynamically generating the tap's config based on the current tenant's username/password. It looks like this might be more difficult in Meltano. Any suggestions?

I see a vars property in the yaml file. And a env_var macro. These could be useful if I run the meltano command with env_var set at the time of running. Do you suggest this, or an alternative approach?