People who were there for the Y2K bug: What was it like living through this? Bonus points if you're a software engineer that was drafted to fix it. Tell me about your experiences! (I'm writing a hypothetical 'What if' book about it)

Was part of company’s Y2K SWAT team. Financial services.

Helped design part of a test environment, completely isolated from the normal network, so alternate dates could be used; basically an alternate universe. Early testing revealed all kinds of problems, not just programs blowing up, but weird stuff, reversing expected behavior (e.g., debiting an interest bearing account instead of crediting it); plus unearthing problems that had nothing to do with the date, that mostly went unnoticed in regular use and testing.

Did Y2K compliance research on every piece of hardware and software in use in the company, which meant trying to find out exactly what company now supported that thing - mergers, buyouts etc. I seemed ot have a knack of finding stuff other SWAT team members could not - (AltaVista, Gopher, etc as search engines - remember this was 90’s, no Google).

I also occasionally represented the company at “street-wide testing” - involving multiple financial service companies data flow. That led to some interesting off the record chats with peers at other companies, and a bit of an underground, sharing.

When Y2K actually hit, there were events, (of course, only in other companies) but a number not officially reported, as actually acknowledging them might damage the reputation of some leading financial companies.