I still don't see why the parent commenter decided to include recovery from cosmic rays as an upside to using Elixir. I'm sure web devs everywhere are throwing out their current tools for this huge advantage! In any case, commodity server hardware already takes care of SEUs through ECC memory.

Memory corruption from cosmic rays may be more common than your intuition suggests. This article cites a 2009 study of a large cluster that found single-bit ECC corrections occurring about 1 per minute per TB, and uncorrectable double-bit errors at a rate of about 1 per year per TB:

http://spectrum.ieee.org/computing/hardware/how-to-kill-a-su....

Whether this is frequent enough to warrant consideration depends on your application, but there are definitely people here who care enough about how their systems recover after errors of this sort that it's not an absurd suggestion.

I use cosmic rays as an example of "errors outside the programmer's control", that's all. My point is that those errors will always exist, and it's desirable to have a backup plan ready.