High Quality Content by WIKIPEDIA articles! The Mastodon Linux distribution differs from most Linux distributions in that it has replaced much of the GNU userland with corresponding tools from FreeBSD. The distribution still uses and maintains the old Linux libc rather than using GNU libc (glibc). This also means that the executable format is a.out rather than ELF. The creator of the distribution currently attempts to build a new release of this BSD/Linux distribution, but an issue raised is that newer kernels are more locked-in to the GNU userland. Also a package management tool is planned. Potentially, classic BSD- or CDDL-licensed UNIX tools, including a package management system, available for Linux in the Heirloom project could be used for a new Mastodon release. Possibly, also the aging Linux libc could be replaced by the BSD-licensed bionic libc.