| Developer | Digital Equipment Corporation |
|---|---|
| Written in | PILLAR, C, SPASM |
| Working state | Abandoned |
| Source model | Proprietary software |
| Marketing target | Minicomputers, Workstations |
| Available in | English |
| Platforms | DEC PRISM |
| Kernel type | Monolithic kernel |
| Userland | VMS and ULTRIX |
| Influenced | Windows NT |
| Influenced by | VAX/VMS, Ultrix, VAXELN |
| Default user interface | DCL, Unix shell, DECwindows |
| License | Proprietary |
MICA was the codename of the operating system developed for the DEC PRISM architecture.[1] MICA was designed by a team at Digital Equipment Corporation led by Dave Cutler.[2] MICA's design was driven by Digital's need to provide a migration path to PRISM for Digital's VAX/VMS customers, as well as allowing PRISM systems to compete in the increasingly important Unix market.[3] MICA attempted to address these requirements by implementing VMS and ULTRIX user interfaces on top of a common kernel that could support the system calls (or "system services" in VMS parlance), libraries and utilities needed for both environments.[4]
MICA was cancelled in 1988 along with the PRISM architecture, before either project was complete. MICA is most notable for inspiring the design of Windows NT (also designed by Cutler) .[2] When the PRISM architecture evolved into the DEC Alpha architecture, Digital opted to port OSF/1 and VMS to Alpha instead of reusing MICA.[5]