Watsonx: IBM's code assistant for turning COBOL into Java

The article title is clickbaity, but the actual point is the proposal of using LLMs to translate large amounts of legacy COBOL systems to more modern languages like Java. Doesn't seem terribly useful to me. I expect you could get a 90% solution faster, but the whole challenge with these projects is how to get that last bit of correctness, and how to be confident enough in the correctness of it to actually use it in Production.

But then all of this has been known for decades. There are plenty of well-known techniques for how to do all that. If they haven't actually done it by now, it's a management problem, and no AI tech is going to fix that.

How hard is it to actually learn COBOL? It seems like a fairly simple language to pick up, but maybe the idiomatic COBOL used in these legacy systems is particularly nasty for some reason.

COBOL is pretty easy to learn. The problem is that it is so full of archaic nonsense (less so with the more recent versions) that you will be tearing your hair out and wishing for something more modern.

COBOL's main value is in maintaining a pile of legacy codebases, mostly in fintech and insurance that are so large and so old that rewriting them is an absolute no-go. These attempts at cross compiling are a way to get off the old toolchain but they - in my opinion - don't really solve the problem, instead they add another layer of indirection (code generation). But at least you'll be able to run your mangled output on the JVM for whatever advantage that gives you.

With some luck you'll be running a hypervisor that manages a bunch of containers that run multiple JVM instances each that run Java that was generated from some COBOL spaghetti that nobody fully understands. If that stops working I hope I will be far, far away from the team that has to figure out what causes the issue.

It is possible that someone somewhere is doing greenfield COBOL development but I would seriously question their motivations.

> that rewriting them is an absolute no-go

Rewriting and expecting 100% feature-parity (and bug-parity, since any bugs/inconsistencies are most likely relied upon by now) is realistically impossible.

However, new banking/insurance startups proved you can build this stuff from scratch using modern tooling, so the migration path would be to create your own "competitor" and then move your customers onto it.

The problem I see is that companies that still run these legacy systems also have a legacy culture fundamentally incompatible with what's needed to build and retain a competent engineering team. Hell, there's probably also a lot of deadweight whose jobs are to make up for the shortcomings of the legacy system and who'd have every incentive to sabotage the migration/rebuild project.