Thanks!

I've finished up there now, so this is purely retrospective.

For them - the workaround (sadly) was -- a lack of testing.

I was really surprised that in a heavily regulated environment (this project faced off to a regulator) Integration testing (which has gotten really easy on the JVM thanks to stuff like TestContainers) just didn't exist.

That could be symptom of a broader lack of a test-driven culture though.