First, my example was fcntl(2), which musl is emulating. So that doesn&#x27;t fit your &quot;rule&quot;.<p>Second, is your &quot;rule&quot; documented anywhere for musl? That&#x27;s what I&#x27;m looking for - an indication by the musl project that such a thing is supported (binary compatibility from newer to older Linux kernels, and if so, what version range).<p>Without such a project-sanctioned statement, I&#x27;m afraid I stand by my position that the blog&#x27;s assertion that the statically-linked rust-musl binary can be copied to any Linux 2.6.x machine (or newer) and just run without any issues.<p>I would agree that any statically-linked rust-musl binary could be built on a Linux kernel and then run on a later Linux kernel, but earlier, well that&#x27;s up to the musl project to say.