I have no informed answer, but not long before you asked the question, a submission was made for what could be a piece of your reliable tech stack puzzle: https

I have no informed answer, but not long before you asked the question, a submission was made for what could be a piece of your reliable tech stack puzzle: https://news.ycombinator.com/item?id=29098183 https://news.ycombinator.com/item?id=29098183 Off the top of my head, maybe Ada/GNAT, MISRA C, CompCert, or Erlang OTP?