Mac OS X Server 1.x/Developer Release 1

From BetaArchive Wiki

Apple Rhapsody Developer Release 1 is a pre-release version of Mac OS X Server 1.x. It was OPENSTEP/Mach with a Copland appearance from Mac OS 8 and support for Java and Apple's own technologies, including ColorSync and QuickTime; it could be regarded as OPENSTEP 5. Two developer versions of Rhapsody were released, known as Developer Preview 1 and 2, these ran on both Intel and PowerPC hardware, though with lacking support for nonstandard hardware. It was available for PowerPC and Intel (works with limited success in VMware, can work well on some PCs from around the time it was made, old IBM ThinkPads work especially well with it).