I like this post from Dave Rupert on lessons from old Russian small nuclear generators:
I wonder if software has a kind of digital entropy, where even good software left untouched for a short timeframe rots and stops working.
@manton I have observed that behaviour so many times. Especially with Xcode projects :-( You just need to touch them constantly to prevent it.
@manton Entropy rate is language-dependent. I have Fortran codes from 50 years ago that compile and run with little or no modification, I have Python code from 5-10 years ago that won't run today without a major overhaul.