Maybe it's the type of companies I've worked for but I have never seen cobol. Anyone know where it's used most?

Any company that knows better has done a modernization to get to get off it asap. The legacy nature of the products means that the few outlets that still support them or their mainframes are charging exorbitant rates. How much? I had a customer (non-gov) that paid a million$ a month to keep their product leased and up on their support agreement, that $12m a year without even talking about the costs of finding Cobol devs. Whos still using them? Any bureaucracy terrible enough to have not transitioned years (decades) ago.

hajile

I know of an insurance company that has tried 3-4 times at a cost probably in the hundreds of millions to switch off COBOL.

The simple fact is that they've spent tons of time slowly coding in hundreds of thousands of little, undocumented edge cases all over the place. The rewrite gets 90% there then falls flat with all the little things and you can't switch these kinds of businesses until it is 100% there.

derefr

It sounds like, rather than a ground-up rewrite, COBOL should be treated as an object-code language, and "hand-decompiled" (ala efforts like https://github.com/n64decomp/sm64) into an HLL that can, at every point, be losslessly transpiled back into the original COBOL.

I know the tooling for doing that doesn't currently exist... but paying someone to develop it would be cheaper than any one of these ground-up rewrite projects!