What percentage of people have the requisite knowledge to do that? The Heartbleed bug was in open source software for over a year before anyone noticed it.

This could be avoided by only running programs written in safer languages. C/++ allows for very very hard to spot bugs that can cause serious issues like heartbleed. You would have to try a lot harder to hide such a thing in a haskell program .

Since all five widely implemented platforms (iOS, Android, MacOS, Windows, and Linux) and most mainstream open source software is written in C, that would be a tough lift. Also since there are far more people who know C than Haskell, that kind of gets rid of the “many eyes” defense.

There may be fewer people able to read haskell but I would say fewer are needed to verify that a program doesn't have unexpected behavior. Also languages like rust are becoming bigger which should help.

Sure there is a lot of C floating around but there is a solution in sight and there is some amount of effort being put in to rewriting things in Rust.