NetBSD pkgsrc
pkgsrc is one of the crown jewels of the NetBSD project. It began life as a fork of the FreeBSD ports tree, but has grown considerably since then. As with the rest of NetBSD, pkgsrc was developed with an eye toward portability, and currently supports a number of operating systems—including the major BSDs, Linux, Solaris, Mac OS X, IRIX, and even Windows.
The portability of pkgsrc has made it popular outside of NetBSD. DragonFly BSD recommends using pkgsrc for installing third-party software; in 2005, Sun made a donation to the project to encourage continued support for Solaris.
Since NetBSD runs on a significant number of platforms where compiling a modest-sized open source project would take many hours or even days, the ability to compile packages to run on other architectures is important. As with the NetBSD base system, pkgsrc packages can be built on any supported architecture, for any other. This extensibility makes it very easy for an administrator to support a heterogeneous network, because the same packages can be built for all platforms from a single server. Even if you’re not compiling packages yourself, pkgsrc can be a good choice for harmonizing userland software across a variety of hardware platforms and operating systems.
NetBSD provides functionality similar to FreeBSD’s portaudit via the audit-packages port, which downloads a list of vulnerabilities and produces a list of installed packages with known holes.