Can some one explain

We have an SaaS app. Pipedream looks really useful. I can see we can make internal API / Integrations. Can some one explain how we can make an integration that our customers can authorize. For example if we wanted to make a QBooks integration our customers could add and authorize - How would that work and is it possible, or would then need a Pipedream account and to pair our APP + QB - Which would be beyond the scope of our users.

If someone can help much appreciated.