&gt; Software like glibc is battle-tested<p>This seems a bit counter-intuitive given that serious problems are still being found years or even decades later.  Perhaps battle-tested is insufficient.<p>And while new code is likely to have bugs, assuming it&#x27;s already based on the original C code it would be less than if it was re-written from scratch based on a spec.  New code can take advantage of the battle-tested nature of the original code even if it&#x27;s in a different language.