Wow. Sudden borderline emergency to do a considerable amount of research and work on some code that I started writing 13 years ago (fundamental libraries and tools written in Delphi then ported to Kylix) and did the majority of work taking it to about 200K lines of Apache .so from 2001 to 2003. I have not touched it for 4 years. FFS, I don't even look at Object Pascal anymore. This stuff runs in a virtual of RedHat 7 because that was the last version of the kernel that Kylix would run on LOL. Hesitation and squinching of the eyes aplenty at the prospect.
But!
I developed my own sort of narrative style of coding where the variables, comments and structure tell a story about 20 years ago. Not that this is any big thing, every coder should do it. But my style is uniquely built for the way I read and interpret. I have to stay *very* disciplined about my coding style because I swear to God if I don't , I don't recognize sh!t I wrote just a couple months ago.
So I opened the projects today and, after a bit of stretching my eyes and fingers around Kylix again for a few I was all over it. Problems averted, code updated. Easily readable, followed the logic through how it builds and executes. And damn, I was good.

Anyhoo: This is the oldest code of mine I've ever needed to open back up and work through. The discipline and extra effort it takes to make sure your code is wired tight is SO VERY WELL WORTH IT. It doesn't matter if it's just a couple lines, you KNOW it will break at some point and you'll have to fix it.