February 2019

I'm looking to switch to a simpler, smaller operating system. If you wrote or know of an OS with these features, please get in touch.
  1. Written in under ~6K lines of C source code. I need to be able to understand and change the OS easily. Smaller is better.

    I happen to use an x86-64 cpu. I'm willing to switch hardware.

  2. No users or groups.

  3. No POSIX interface. The smaller the API the better.

  4. Boot and run only one process: an application that I'll write.

  5. Multi-threading: I want to run multiple C functions in parallel. I prefer a SASOS, where all threads run in the same address space. I can guarantee threads can't corrupt each other.

  6. A way to send data to other computers. This doesn't necessarily mean writing network card drivers.

    Could there be a network driver that works with all computers? Narrower is better: how about with only one USB-to-wifi card?

  7. No text editor. (I know I'll need one, but not in the OS.)

  8. No shell, no command-line utilities, no applications.

  9. Run in text mode by default.

  10. (Optional): a way to draw on the screen. It's ok if the OS works only in VGA mode.

  11. No window manager.

  12. (Optional): a way to read/write data. This doesn't necessarily mean a filesystem or a hard drive driver. It's ok if data are sent to other computers to be saved, or saved only on USB sticks.

  13. It must have testcases.

I want a system small enough that I can program everything in it.