[StevePerkins]

Around 2000, I spent some time developing snazzy new Java e-commerce stuff, at a large company that was mostly based on midrange AS/400's running RPG code. At the time, they announced a huge project to retire RPG and re-write everything in Java.

I've stayed in touch with some friends there all this time, and apparently they still haven't finished this project as of 2020. Disaster after disaster.

The first executive couldn't execute, so he moved on and the project was slow-rolled for awhile. Until enough time had passed for a subsequent executive to claim it as HIS "fresh new idea".

That executive came it very aggressively, actually pushing out all of the RPG employees and contractors well before the company was really ready. So that executive was pushed out, and his replacement had to hire IBM Global Services to come in and take over everything. IBM hired most of those employees and contractors who were let go. So the net result was the same people doing the same job, with the company paying 2-3x more than they had been paying.

It was around 2015 when they finally reached the tipping point, to where the company was "a Java shop with some legacy big iron" rather than "an RPG shop with some Java e-commerce pieces". But there's still a lot of AS/400 on the inventory side of things, and it will probably be another couple of decades before that finally goes away.

A lot of people on HN and Reddit, who are either students or startup employees, just have NO IDEA how things work for large businesses in the other 49 states. Stuff lasts forever, it's just a completely different world.

[7thaccount]

What people fail to understand is that the rules/logic of a particular business that has been around for awhile can be absolutely enormous, complex, and poorly documented outside of the thousands of lines of code in production systems .A lot of this is due to historical choices that nobody remembers why a decision was made, but another problem is that many employees hate documenting what they know as it is either boring or they think it makes them less valuable, and management usually doesn't push it because it isn't a big quantifiable win on their resume and most aren't going to stick around long enough to see the fallout from the loss of institutional knowledge over time and turnover. Rewriting can be very challenging even with the domain knowledge, onboarding people to be competent in the business can take close to a decade... etc. They're kind of like programming languages where there is no spec other than the interpreter.