To build the system (experts only):

• Your build environment must be FreeBSD 9.2-RELEASE (building on FreeBSD 10 or 11 is not supported at this time).

• an amd64 capable processor. 8GB of memory, or an equal/greater amount of swap space, is also required

• You will need the following ports/packages when compiling anything FreeNAS-related:

  • ports-mgmt/poudriere-devel
  • devel/git
  • sysutils/cdrtools
  • archivers/pxz
  • lang/python (2.7 or later, with THREADS support)
  • emulators/virtualbox-ose
  • sysutils/grub2-pcbsd
  • sysutils/xorriso (and all the dependencies that these ports/pkgs install, of course)

• Checking out the code from git:

% cd /path/to/your-build-filesystem
% git clone git://github.com/freenas/freenas.git
% cd freenas

• Build it

% make git-external
% make checkout
% make release

• Update the source tree, to pull in new source code changes

% make update

This will also fetch TrueOS and ports for the build from github.

If your build completes successfully, you'll have both 32 and 64 bit release products in the release_stage directory. You will also have a tarball in your build directory containing the entire release for easy transport.