Debian GNU/kFreeBSD is an operating system released by the Debian project. It uses the kernel of FreeBSD combined with a GNU based userland and glibc. The majority of software in Debian GNU/kFreeBSD is built from the same sources as Debian GNU/Linux. The k in kFreeBSD is an abbreviation for kernel of, which refers to the fact that only the kernel of FreeBSD operating system is used. The Debian project maintains two ports based on the FreeBSD kernel, "kfreebsd-i386" and "kfreebsd-amd64".
Debian developers have cited OSS, pf, jails, NDIS, ZFS and central management of code licenses as reasons for being interested in the FreeBSD kernel.
Debian GNU/kFreeBSD was included in Debian 6.0 (Squeeze) as a "technology preview", and in Debian 7.0 (Wheezy) as an official port. Debian GNU/kFreeBSD will not be included as an official port in Debian 8.0, due to insufficient quality, though the release managers hope it will be released simultaneously as an unofficial release.
The Debian popcon registers the usage of a subset of Debian users. As of April 2015, popcon registered 96 (0.05%) kFreeBSD users, compared to 21 (0.01%) HURD users, 129 (0.07%) unknown users, 175,464 (99,86%) Linux users and 175710 users in total.