This post shows how to apply the Drain filter abstraction to the master branch of the Pluralsight course about A Functional Architecture with F# by Mark Seemann.
As the diff-output shows, applying filtering with Drains cuts the maintenance of multiple homogenous abstractions, and makes the code cleaner and easier to reason about.
To apply the diff, access the source code by getting a Pluralsight subscription which is totally worth it for this course.