(SVR4). The project was released under the name Solaris, which became the successor to SunOS 4 (although SunOS 4.1.x micro releases were retroactively named Solaris 1).

ZFS was designed and implemented by a team at Sun led by Jeff Bonwick, Bill Moore, and Matthew Ahrens. It was announced on September 14, 2004, but development started in 2001. Source code for ZFS was integrated into