Push on Firebase, everything else on AWS

A two-cloud setup chosen for one feature, and what it costs in configuration.

Auth and the API lived on AWS. Push notifications went to Firebase Cloud Messaging, because that was the path with a working client library on both mobile platforms the week it was needed.

The cost is permanent: two projects, two sets of configuration files in the build, two consoles. The benefit was shipping the feature that week. I would make the same call again.

Takeaway

Write down at the time that it was a shortcut, so that the next person does not mistake it for a design.