I was a programmer for a large school district in the bay area from 1996 to 1999. What a great way to cut my teeth professionally!<p>Yeah, it was a big deal. Pretty much all dev work was done by me and one other guy. How much dev work could a school district have back then? Oh, lots. Every school, and in some cases individual educators, would send in requests for various reports, and each one required configuring a mainframe job, running it, and doing some kind of thing with the output (conversion to a "modern" format on a 3.5" disk or printing it or something). Every payroll cycle required a lot of manual labor, every report card cycle, there were daily student attendance jobs, and this particular district had a rather advanced, for the time, centrally-managed network across the entire district with Solaris DNS.<p>So on top of all this regular workload, we had to go over pretty much every single line of COBOL in that mainframe, visually, and search for Y2K-related bugs. There were many. The Solaris box needed to be patched too, and the first patches that came out weren't great and I didn't know what I was doing yet either.<p>So we started on this in earnest in Summer of 1997, while everyone was out of school. We ran a lot of test jobs, which involved halting all regular work, monkeying around with the mainframe's date, and then running a payroll job to see what blew up. By late 1999, my mentor there was pulling multiple all-nighters. He had a family of his own too and it really impacted his health.<p>There were mountains of greenbar printouts in our little office, all code, with bright red pen marks. Such was life when working on a mainframe at the time. The school district also brought out of retirement the guy who had written much of the key operating system components for our mainframe. I believe he came on as a consultant at rates that would be pretty nice even by today's standards.<p>In the end, school restarted after winter vacation and most things ran okay. A few jobs blew up where we had missed something here or there, but everyone by then had got sort of accustomed to the chaos and it just needed a phone call to say, "it broke, we're working on it, call you tomorrow".<p>Rough estimate, there was probably over a thousand hours' worth of labor to fix it all. Had that not been done, virtually nothing in that school district would have worked correctly by the beginning of 2000. (Some things started failing a month or two in advance, depending on the date arithmetic they needed to do.)<p>And these weren't just "year 100" printer errors; a lot of things simply barfed in some fancy way or another, or produced nonsense output, or -- in the most fun cases -- produced a lot of really incorrect data that was then handed off to other jobs, which then produced a lot of even more incorrect data, and then saved it all to the database.