This makes NetBSD the 6th OpenZFS platform, after Illumos, FreeBSD, Linux, Mac OS X and OSv. The 7th if you include the under development Windows port:
But has never been stable. The root device vops look-up would cause kernel panics. Never worked out why. There has been some new efforts to make it useable though.
https://github.com/openzfsonwindows/ZFSin