Multi-decade Stability

One of the failures of the widespread silicon - software technology surrounding us is it is very short lived. Ad-hoc reboots, battery replacements, even device replacements are part of our daily lives. Software updates used to be a nightmare too, but thanks to the widespread connectivity they have become less annoying, moving to the background.

This is interesting like the continuous improvement in software maintenance and testing has made this task that was so annoying and tedious a much more bearable operation. Something that has become fully automatic, to the point is is almost invisible. None of us can say today which software version is running on their phone or a personal computer. The answer is - probably the latest.

So we may say the software problem has taken care of itself, as vendors will continue delivering in the background well-tested upgrades, as long as it is economically feasible for them. And when it becomes not feasible, the device is left on its own. As long as it can perform the functions being disconnected, it may continue working "forever" (from the software perspective).

Disconnected software does not age. Unlike hardware.

Ageing hardware is a different problem and surprisingly it seems more difficult to solve. Contrary to what we typically think, electronic components do not live forever. Even setting batteries aside, there is this huge, huge problem of electrolytic capacitors. They dry out over time and a dry capacitor will render any electronic device useless or even dead at some point in time.

I have a substantial collection of vintage radios and in a rare event of having a spare time, I try maintaining them in working order. Careful enough not to leave any batteries inside (batteries always leak - zinc or alkaline) or burst (lithium). This actually is the easy part - does not require a soldering gun and disassembly. But there is very little you can do to prevent capacitors from dying out. In some units I have replaced electrolytic caps with tantalum ones, which should last longer. But most original units are almost dead not, despite not being used.

Similarly the home automation system I put in place 10 years ago keeps working, as I have upgraded most of the battery - powered devices to harvest solar energy and use supercapacitors for storage. Supercaps are much safer compared to any battery technology and they supposedly live "forever". 

Which brings me to the point - how do we define "forever", as long as technology is concerned? Is 10 years enough to be considered "forever"? Or 20 years? From my own experience 10 years is way too short. My car is 15. The weather station I look at daily is 12. The home automation turned 10 a few months ago. I would like to continue using them for the next decade or two. Certainly with the solar-powered supercap-based occupancy sensors this seems to be possible.

But then - how to test this? If my hardware mods start failing in 15 years, and I find the root cause and be able to address it - how do you approach multi-decade stability testing? A software / hardware project that spans across multiple generations?

Yes, I'm a dreamer :) But this is a very interesting challenge... How to achieve multi-decade stability of devices which include electronic and software components? Our technology - based civilization is extremely fragile. It will immediately revert itself to the Dark Ages when not maintained...