This reminds of of this article<p><a href="http:&#x2F;&#x2F;www.joelonsoftware.com&#x2F;articles&#x2F;fog0000000007.html" rel="nofollow">http:&#x2F;&#x2F;www.joelonsoftware.com&#x2F;articles&#x2F;fog0000000007.html</a><p>Apparently Microsoft&#x27;s Excel team had even written their own C compiler.