Why Reliability Demands Functional Programming

Re:Why Reliability Demands Functional Programming by stingraycharles on Saturday December 27, 2025 @11:48PM (#46408548)

Honestly, as someone else who does a lot of data plumbing, there is so much FTP servers with excel sheets being used as the means for official clearance processes.

There are constant data bugs in the feeds provided by major exchanges, market makers, etc, and so many iffy business rules that are basically all encoded in 100+ tab excel sheets.

Maybe this article focuses on a very specific niche of banking, but most of it is tied together with FTP and excel sheets.

I think the author would be shocked just how flaky a fundamental banking protocol like SWIFT is.

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Re:Why Reliability Demands Functional Programming by rastrian on Saturday December 27, 2025 @11:52PM (#46408571)

I’ve worked in Brazilian banking stacks that were literally FTP + spreadsheets for years. So yes, the ecosystem is often messy and protocols can be flaky.

That’s exactly why I argue for stronger internal modeling: when the boundary is dirty, explicit state machines/ADTs + exhaustiveness + idempotency/reconciliation help ensure bad feeds don’t silently create invalid internal states.

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Re:Why Reliability Demands Functional Programming by whateveracct on Sunday December 28, 2025 @03:06AM (#46409344)

I totally agree as a fellow fintech engineer. It was a battle getting approval for all that from Product for us. While we were battling for it, we rushed multiple projects without literally any of it. And then spent a year+ each time cleaning up the mess.

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Re:Why Reliability Demands Functional Programming by brabel on Sunday December 28, 2025 @01:54PM (#46413437)

And your pockets were being filled in that year while you were just doing cleanups. Mission accomplished.

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