I hope you're right, but many comments here on HN suggest their experience with mainframes is very different. z/OS and its predecessors provided so many services completely transparently to the application that a mainframe to modernity migration is doomed to fail unless it can completely emulate (or design around) the capabilities provided by the OS and other subsystems.

Even ignoring the needs of the super high end customers like banks (eg, cpus in lockstep for redundancy), being able to write your app and just know that inter-node message passing is guaranteed, storage I/O calls are guaranteed, failover and transaction processing is guaranteed, just raises the bar for any contender.

K8s is wonderful. Can it make all the above happen? Well, yes, given effort. If I'm the CTO of an airline, do I want to shell out money to make it happen, risk it blowing up in my face, or should I just pay IBM to keep the lights on, kick the can down the road, and divert precious capital to something with a more obvious ROI? I think their "no disasters on my watch/self preservation" instinct kicks in, and I can't really blame them.

HN thread:

https://news.ycombinator.com/item?id=36846195

[I work as a SA] . There are many companies that don't have a original COBOL source code only compiled objects which has been running for more than few decades. How can you guarantee that it will run perfectly in k8s . Major companies can never take that risk unless you give them some insurance against failure

There is a major drawback to this approach -- you need to have somebody who knows what they are doing. Total deal breaker in most of the places that have this problem in the first place.

This is fascinating to me as an ex-mainframer that now works on a niche hyperscaler. I would love to learn more!

Will you let me know some of the names in the space so that I can research more? Some cursory searching only brings up some questionably relavent press releases from IBM.

Yup, but the COBOL application doesn't know you've done that.