Tinderbox is a package building system for FreeBSD that has been modified
for use on pkgsrc on DragonFly BSD.  Joe Marcus Clarke is the author.

One can define multiple jails (base system versions) and multiple portstrees
(portstree = pkgsrc tree).  The combination of jail and portstree is called
a build.  A Tinderbox jail is not what is understood as a jail in *BSD, it
is in fact a given world in a chroot.  Tinderbox supports automatic tracking
of dependencies and only rebuilds packages that changed since last run.
Tinderbox has support for email notification of failed builds.

Tinderbox is designed to easily provide package sets of needed ports for
specific platforms and architectures.  Tinderbox is an excellent tool for
testing new packages and package upgrades, especially for testing
dependencies and packing lists.  It is also useful for testing packages on
previous releases of *BSD since it's possible to run a previous release
world inside a jail on a current release host.

Tinderbox/pkgsrc site: http://github.com/jrmarino/pkgsrc-tinderbox