Comment by signal11

There are a few shareholder-friendly patterns to get this done, but it is domain-specific. I’d say it’s more “rip off the bandaid slowly and carefully”.

Eg a common one is to wrap a new no-op new service around the old one, and gradually replace parts of the old one (the “strangler fig pattern”).

This is technically great, but it’s also financially great because you are don’t spending large sums on a big-bang rewrite. You’re spending relatively small sums on a “pay as you go” basis, something board members and shareholders do like.

But of course this depends on how your systems are set up.