Kris Moore, FreeBSD contributor and spear-header of the ZFS on FreeBSD project, announced a Call for Testing of the latest development built on FreeBSD 12-STABLE. You can download the ISO from the link below. In other recent news, a TrueOS inspired package base for FreeBSD has also been uploaded for testing.

We're pleased to make available images allowing testing of FreeBSD using ZFS
on Linux.  During this development cycle, the ZoL code has been made
portable, and available in the ports tree as sysutils/zol and
sysutils/zol-kmod, for userland/kernel bits respectively. While some have
used these for testing, we felt it necessary to generate some installation
images which are an easier method of getting up and started using ZoL. These
images are built against FreeBSD 12-stable and 13-HEAD and will install a
world / kernel with the base system ZFS disabled and the sysutils/zol ports
pre-installed. 

It is possible to these with both UFS or ZFS on root, and we're looking for
feedback on any stability issues or other regressions that you see vs the
legacy ZFS in base.

CFT for FreeBSD + ZoL

https://lists.freebsd.org/pipermail/freebsd-stable/2019-April/090915.html

I'm pleased to announce a CFT for builds of FreeBSD 12-stable and 13-current
using "TrueOS-inspired" packaged base. These are stock FreeBSD images which
will allow users to perform all updating via the 'pkg' command directly.
Rather than trying to answer all questions in this announcement, we've
created a FAQ page with more details. Please refer to this page, and let us
know if you have additional questions that we can include on that page going
forward.
Additionally, I will be hosting a Package Base working group at BSDCan 2019,
and welcome user and developer attendance to discuss this and other ongoing
package work:

CFT: FreeBSD Package Base

https://lists.freebsd.org/pipermail/freebsd-stable/2019-April/090963.html

Related links:

Phoronix: https://www.phoronix.com/scan.php?page=news_item&px=FreeBSD-Pkgbase-CFT 

CFT: http://callfortesting.org/