&gt; until you&#x27;ve had to use autotools or custom build a makefile for a half dozen different C compilers, kernels, libc, and so on, you don&#x27;t know from POSIX &quot;standards&quot; pain.<p>Truer words have ne&#x27;er been spoken. My first big boy job involved building and maintaining a large open source stack on top of AIX. These days I occasionally experience hiccups related to OpenBSD not being Linux. Problems aren&#x27;t even in the same league. That said, the thrill of getting stuff to work on AIX was certainly greater (and purchased with more human suffering).