The Apple-sponsored ZFS implementation, first available as a read-only kernel extension in 10.5 and later in the developer builds of 10.6, was unceremoniously yanked from the shipping version of Snow Leopard (10.6), after a lengthy hiatus from the open-source project hosted at the (probably now defunct http://zfs.macosforge.org). A nabble backup of the old mailing list is available at http://n3.nabble.com/Mac-OS-X-ZFS-Discuss-f19757.html

Since ZFS adopted a dedicated following under Mac OS X, there's a desire to keep this project going; this code project will be used to record issues and ongoing development (if any) of this extension.

Please note that ZFS is licensed under Sun's CDDL.