Dinghy index concept papers

System Niches

Explore a range of niches that computer systems fit into.

Niche/0: Dinosaurs

    Mainframes, Minis.

    Defined the era when computing was expensive.

    Buy-in cost more than the average annual wage, with further ongoing costs,
    and the installation dominates a room.

Niche/1: Real-time systems

    Platforms that must work well.
    Many have life-and-death stakes.

    Key qualities

        Device should never cease working correctly.

        Common use of timing guarantees, which must be met.


        Computers driving manufacturing equipment

        Drive systems in motor vehicles

Niche/2: Early home system

    Console driven system with no network.

    Typically: 8-bit word-size, 16-bit address size, small ROM kernel offering
    a BASIC repl.

    Modern take on this genre,



Niche/3: Racing dinghy

    Responsive, single user systems.

    Key qualities

        Developer interacts with the system bedrock.

        Sound and graphics

        Small kernel with support for multitasking

        Lightweight desktop, if any.

        User is all-powerful

        System ships with tools for interacting with the bedrock.

    Historic systems tended to be weak on the last point.


        Amiga. Well-architected platform. Bundled dev tools were weak, but
        sufficient for a skilled user to bootstrap. Strong third-party tools

        Atari ST. Well-architected platform. Did it ship with dev tools?
        Strong third party tools available.
    Other systems that fall short,

        Apple IIGS. Bundled dev tools were weak, but sufficient for a skilled
        user to bootstrap. Better after market tools were available. Limited
        by legacy constraints of being an Apple II system. Strong audio. 

        MacOS Classic. System came with no dev tools. Original arch was 68k,
        similar to Amiga/Atari. After System 7, you could install python to
        break out of the sandbox and do as you liked. Tutorial for creating a
        dev env in emulation, http://beyondloom.com/blog/thinkc.html

        VGA PC era. DOS, OS/2, Win95 and Win98 shipped with a quirky machine
        code monitor. Even by the birth of the 386, the PC platform was awash
        with legacy complications (e.g. a20, gdt, 640k barrier), increasing
        the barrier to entry. Batch and REXX could be used for scripting.
        Strong third-party tools available, some at low cost (Turbo Pascal).
        Sound blaster became a defacto standard late in this platform's life.
        The game Transport Tycoon illustrates the power and flexibility that
        were possible on this platform. Example of a no-tools bootstarp on
        DOS: https://github.com/mniip/BOOTSTRA.

        JVM, CLR. You can build a universe within these systems. A challenge:
        they tend to live on top of yachts. With a lot of effort, you can
        create a stripped linux foundation and achieve a high level of
        mechanical sympathy. Examples: LMAX, INET.



    Past systems of this form were vulnerable to malware. This is not an
    inherent flaw of this niche. Consider if we created a multiprocessor
    system, with limited memory maps. You could sandbox a process to a
    specific core with a limited memory map.

    There have not been any strong examples of this category since ubiquitous

    Introducing networking to a dinghy presents several special challenge:

        Finding a balance between synchronous and asynchronous concerns,

            For responsiveness IO, a dinghy will tend to bring a synchronous
            attitude to IO. For example, polling to see whether the down arrow
            key is currently depressed.

            But networking is most effective when it is asynchronous. Example:
            requesting a call-back when a new message arrives.


            Once you are on the network, security becomes a high priority,
            because it is so easy to get owned. The successful Windows 95/98
            line of computers were killed off essentially over this issue in
            favour of Microsoft's yacht platform, Windows NT.

    Perhaps the ideal racing dinghy will have no network ambitions. if it has
    powerful enough local tools, does it need to live on a network?

    In the eighties and nineties, RAM was expensive. In 2020, RAM is cheap. It
    should be possible to do clever things with plentiful RAM.

Niche/4: Yachts

    Mainstream workstation/server bracket.

    Key qualities

        CRUD filesystem.

        Multi-user design aimed at an academic or enterprise setting. Heavy
        emphasis on permissions.
        Users are treated as guests. There is clear separation between kernel
        and userland.

        Userland interacts with the kernel via a synchronous API.

        Variety of local-IPC mechanisms.

        An emphasis on some mix of cheap-processes and multi-threading. These
        mechanisms allow the system to achieve multicomputing despite the
        design weight of everything above.

        As a result of everything above, a large kernel written in C.

        Complex software installation arrangements.


        Modern Unix. BSD, System-V descendants, Minix, OSX, Linux, etc.

        Windows NT.
        BeOS/Haiku, although is not multi-user.

    Note that Minix does appear in the Unix group above. As a microkernel, it
    moves some code out of the kernel. But as a platform, it pays the same
    design taxes.

    Gravity towards C/C++

        C for the kernel. Allows developers who to reason about and debug
        large kernels.

        C++ for userland, particularly flagship applications. Office,
        photoshop, browsers, cad systems, video production tools.

    Yacht filesystems are quirky.
        On some levels, they look sophisticated. We have NFS and CIFS. We can
        partition then in neat ways, and mirror, and there are clever
        mechanisms to defend against corruption.

        Yet, our interactions with them are awkwardly synchronous. Consider
        the hassles involved in closing a file that might be on a remote
        system without jamming the application.

    Imagine a world where TCP had happened before hard disks. Perhaps we would
    say "everything is a stream" rather than "everything is a file", and would
    engage with our kernels using messages rather than synchronous API calls.

    The historic cost of RAM may also be a factor in the synchronous habit.

Niche/5: Personal Device

    Phones and tablets have their own niche, the Personal Device.

    Key qualities

        Feel matters.

        Sound and graphics.

        Developers cannot directly interact with the underlying machine.

        User is sandboxed in a simple process model. May not have a

        Weak IPC


        Teenage Engineering OP-1. Pure example. This is a synthesiser built
        from first principles. It runs some kind of minimal operating system
        on custom hardware. Low-enough latency software system, beautiful
        small display, responsive controls let users craft waveforms.

        Apple iOS. Apple control the whole stack and have created a platform
        that is able to run commercial quality audio tools.

        Android. Android is a less pure example. It is a Java shell on top of
        a linux derived OS. It is not well-suited to low-latency audio work.

        OTTO. This is an attempt to build a device similar to the Teenage
        Engineering OP-1, on top of a Raspberry Pi running Linux. Given the
        difficulties that Android has had, it will be interesting to see
        whether they can make this work. Might Arduino be a better foundation?

        Games consoles from Atari 2600 to Nintendo Switch.

Niche/6: Single System Image

    Distributed computer built from commodity hardware, and operated by a
    single party.

    Key qualities

        Single interface to a system composed of multiple computing nodes.





Niche/7: Consensus network

    Distributed computer operated by multiple parties.

    Key qualities

        Strong emphasis on achieving consensus between nodes.




    Word-processors of the 80s. Canon cat, Brother devices.

    Plan 9. Seems half way between a Yacht and a Single System Image.

    Oberon. Where does it fit? Yacht ambitions?

    kOS. Where does it fit? (As of 2020, seems to have been abandoned?)

    BaremetalOS. Aimed at the HPC domain. Strong mechanical sympathy goals.
    Does not contain its own dev tools, no sound or graphics.

    RMoX. This is an OS platform written in an obscure asynchronous systems
    programming language called Occam. It may have strong potential as a
    dinghy foundation. Links to the source code are broken at the time of
    writing. https://www.cs.kent.ac.uk/projects/ofa/kroc/rmox-cpa.pdf