Oh I am sure with the right prompts and the right chunking and subagents this is already possible today. But converting the old cobol mess to java code that is "most likely doing the same things" is just a fraction of the work.

You need to run those systems in parallel, integrate them in each other or have an abstraction/two-rails layer in front of them, test, test, test and test again, all of which takes months, while new features now need to be added to both systems, whether by AI or some average developer schmuck!

Do you have any idea how much any of this costs? Mind boggling amounts of money. Infrastructure costs will at least DOUBLE for several MONTHS. Meanwhile you will need extra manpower and AI credits for MONTHS on top of your increased existing costs for maintenance and new features.

Welcome to a new hell! LLM can't solve this!