Let me surprise you, with the code quality that sometimes is running in what is actually &#x27;life-critical&#x27; software.<p>Back in the nineties, I wrote a nice piece of some 300kb of C code, for DOS&#x2F;x86.  It was a complete software package, controlling medical equipment that was testing speed of blood coagulation. These tests are crucial in the patient post-operation recovery.<p>This piece of C code had some hardware control code, some statistics, a bit of math, some visualisation, GUI, etc. Normally, you&#x27;d imagine a team of 2-3 people, carefully written test cases, dedicated QA person, and a year of time to write something like it. And independend lab, that would certify the thing.  Well... in that case, yes, there was independent certification... but...<p>It was just one developer, and I was 13, when I wrote it ;) During after-school time, in around 4-6 months.  And I must say, I still sometimes have chills, when I think of the code quality, and, um, unorthodox solutions of 13-year-old myself. Yes, I&#x27;ve had some years of experience at the time, both writing software and designing hardware, and advice from my parents, who both could write software. But, at the time, I&#x27;ve had zero formal training, aside from reading K&amp;R and PC XT manuals ;).  So, you might imagine the code quality ;)  Even, no need to imagine, I actually still have it somewhere in the archives :)