[DaiPlusPlus]

I agree with your assessment: desktop-browser online banking (with US banks in particular) is a depressing experience given how they’re full of ads for credit-card offers and manual (if not broken) OFX/QFX downloads that only contain a fraction of the actual backend txn data that the banks won’t ever share with their (retail-banking) customers…

And yet, while lots of banks now use SMS 2FA, none of the banks I use (Chase, BoA, Citi, and a couple of credit-unions) offer the far more secure TOTP scheme, let alone any way for headless clients to download txn data except via the literally-25+-years-old Quicken/Intuit OFX endpoints - presumably without 2FA, but with zero documentation in their online help and their retail banking customer support people have no idea what I’m talking about when I say OFX - it’s maddening,

lots of banks’ legacy OFX endpoints are listed here: https://www.ofxhome.com/index.php/home/directory

[scott00]

What else is in the backend transaction data?

[DaiPlusPlus]

LOADS of data - especially for industry-verticals that have heavy integration with credit-card companies (e.g. airlines include ticketing and even seat info in the metadata they submit to banks: this dates back to how air-miles rewards cards originally worked in the late 1980s) and there was tight integration between banks and airlines - even (or so I'm told) to the point of where banks' in-house "main" databases and ssytems have dozens of very, very hardcoded fields because of that early collab work - which then ossified in-place and now everyone's too scared to remove those now unused fields for fear of breaking everything.

...which leads me to believe that Cobol does not lend itself well to unit and integration testing in isolation then.