MacZFS provides a mirror of the official project page for the premiere free ZFS implementation for Mac OS, known as MacZFS.

Current Status

Supported systems: PowerPC and Intel, 32-bit and 64-bit, Mac OS 10.5/10.6/10.7.

The official mailing list, wiki, and other resources exist at this site. The IRC channel is called #mac-zfs on

The software consists of a stable release based on onnv_74 which provides zpool version 8 and zfs version 2, and development releases based on onnv_75 and onnv_77. Zpool version 8 is about a year or two behind the mainstream free release found in OpenIndiana, but is nevertheless a highly venerable, stable, widely tested, and mature product. It originates from a timeframe where ZFS was already almost ten years mature, and was already several years beyond virtually any other storage platform.

The completely free MacZFS 74 provides absolutely all functionality, speed, and data integrity guarantee which are needed for personal and small enterprise use. We believe it to be one of the most advanced storage solutions for most Mac OS users, at any price.

Ten's Complement

The MacZFS community would like to welcome Ten's Complement to the scene, who have released a more recent port. We look forward to joining with their effort, pending the release of their source code.

Project History

Years ago, Apple began the visionary and ambitious undertaking of porting ZFS to Mac OS. The company distributed ZFS as a read-only kernel extension in Mac OS 10.5 and later as a fully functional suite in the developer beta builds of Mac OS 10.6. Apple hosted the project at the now defunct; the now defunct original mailing list is now mirrored at Nabble. After a lengthy hiatus from the public eye prior to the final release of Mac OS 10.6, the company unceremoniously withdrew their involvement from the ZFS community both internally and publicly, by suddenly deleting all traces of ZFS from Mac OS and from their web sites.

Explanations for this action involve a failure to achieve a private licensing agreement between Apple and Sun over the ZFS source code. This was severely exacerbated by overarching legal aggression from Net App toward Sun, and hence toward Sun's customers such as Apple.

Forever grateful to Sun and Apple and to all of their brilliantly visionary engineers for the generous head start, the community fearlessly resumed the project's development. The community reacted immediately to the disorienting setback by mirroring all historical resources, by opening this project page, and by starting various personal source code forks. Development has ensued in the years since.

The summary result of all of these efforts made by Sun, Apple, and the MacZFS community is the drastic advancement of the state of the art of storage technology on Mac OS. One of the former Apple staff members who spearheaded that effort, has reconstituted his efforts as Ten's Complement.


The original ZFS is licensed by Oracle under the CDDL and "ZFS" is a registered trademark of Oracle America, Inc. "Macintosh" and "Mac OS X" are registered trademarks of Apple, Inc. Portions of MacZFS are copyright by various individuals.