I worked on a few systems back around 2000 that were still in use up until the company entered new management in 2016 but no one working there after I left knows how they work. I left them significant documentation and recovery files on multiple different medias and they've managed to misplace/lose both. They phoned me twice in a panic in the years since because of that hah.
One of the things that seems to have thrown everyone that worked on it since is that I used some bitwise "encoding" to pack a lot of information in respect to information with static ranges like dates into smaller chunks of data that can contain the results for multiple values in one variable - even with documentation pretty much everyone who has touched it since doesn't seem to understand how to separate out the values again.
We've one option that we still sell that was written by a bloke that's now director, no one really knows how it works but him and we're not allowed to ask if we need clarification on anything... I've touched on bitwise briefly so far, lots of info online about it so I'm shocked people can't get it especially if you've documented it! We don't really do documentation, "it's out of date too quickly to both!". We've some basic procedures but they are old or inaccurate, and when updated they are done as a planned request for noobs who don't know how it works. I've started documenting things myself using snippets like a kind of snippet wiki
I really want to work for a company with kick-ass training, that recognises potential and is eager to invest in people. I hear people saying how amazingly well I've done in the 16 months I've been here, seen no one pick it up as fast but in all honesty, I constantly doubt my own abilities and feel like an imposter.
