maximum entropy" through "operating systems unification at last" and wanted to lay a new worldview for the future of computing. IBM sought a new world view of a unified foundation for computing, based upon the efficient reuse of common work. It wanted to break the traditional monolithic software development cycle of producing alphas, then betas, then testing, and repeating over the entire operating system — instead, compartmentalizing the development and quality assurance of individual unit objects. This new theory of unifying existing legacy software and the new way of building all new software, was nicknamed the Grand Unified Theory of Systems or GUTS. Coincidentally, Apple already had a two-year-old secret prototype of its microkernel-based object-oriented operating system with application frameworks, named Pink. The theory of GUTS was expanded by Pink, yielding Workplace OS. Architecture IBM described its new microkernel architecture as scalable, modular, portable, client/server distributed, and open and fully licensable both in binary and source code forms. This microkernel-based unified architecture was intended to allow all software to become scalable both upward into supercomputing space and downward into mobile and embedded space. Leveraged upon a single microkernel, IBM wanted to achieve its grand goal of unification by simplifying complex development models into reusable objects and frameworks, and all while retaining complete backward compatibility with legacy and heritage systems. Multiple-library support would allow developers to progressively migrate select source code objects to 64-bit mode, with side-by-side selectable 32-bit and 64-bit modes. IBM's book on Workplace OS says, "Maybe we can get to a 64-bit operating system in our lifetime." IBM intended shareable objects to eventually reduce the footprint of each personality, scaling them down to a handheld computing profile. At the base of Workplace OS is a fork of the Mach 3.0 microkernel (release mk68) originally developed by Carnegie Mellon University and heavily modified by the Open Software Foundation's Research Institute. Officially named "IBM Microkernel", it provides five core features: IPC, virtual memory support, processes and threads, host and processor sets, and I/O and interrupt support. On top of the IBM Microkernel is a layer of shared services (originally called Personality Neutral Services or PNS) to cater to some or all of the personalities above them. Shared services are endian-neutral, have no user interface, and can serve other shared services. Byte summarizes that shared services "can include not only low-level file system and device-driver services but also higher-level networking and