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@timbray how many COBOL codebases have good test suites? I suspect none.

How well do LLMs do without tests / types / guardrails?

Best practice AFAIK is to run in parallel with prod. I guess they could try that, but it would take like a monthly billing cycle or a quarter to test one change.

@timbray

> COBOL systems are so old that any viable alternative becomes immediately attractive.

A tech journalist said that. We're doomed, if we cannot build IT infrastructure that can last for decades.

Good news is we can.

Bad news is there is more profit in new crap than in maintaining the existing infrastructure

Software, generally, socks mostly for that reason. And they are laying off all the computer programmers...

@timbray

What could possibly go wrong.

I worked on those COBOL systems for much of my programming career. Made good living maintaining 60s and 70s spaghetti code (literally. the comments were all in Italian. I'm not kidding).

Having AI guessing what the code might look like should give chills to everybody who uses money.

@timbray "If Anthropic's Claude or other large language models can understand, maintain, modernize, or even replace COBOL systems…"

That "If" is doing a LOT of heavy lifting!