TomatOS

An experiment for writing a kernel with C# drivers and usermode, with a fully featured dotnet runtime running on baremetal with the main goal of using Type safety for memory safety.

Unlike other baremetal C# runtimes out there (For example Cosmos) we have a full garbage collector and JIT support in the kernel itself, so stuff like reflection/emitters and more will eventually be available for apps to use.

Progress

Kernel itself

• Memory subsystem
  • Freelist based physical memory allocator
  • TLSF based kernel heap
  • Single address space management
• Threading subsystem
  • Lightweight threading
  • Mostly copied (translated) from Go
    • Scheduler
    • Synchronization primitives
    • Timer subsystem

Dotnet Runtime

We are using our custom dotnet runtime called TinyDotNet, for progress on it see its README

OS Design

• Everything runs in a single cpu address space
  • Threads are super light-weight and different assemblies have no context switch overhead.
• Safety by Type system
  • Accessibility/Visibility is enforced by the kernel at JIT time
    • If you don't have access to a field you have no way to get its value
  • If you don't have a ref to an object and you can't create it yourself, you won't have any way to get a reference to it
• Each assembly has one global instance, for GUI apps the window serveris going to simply notify you that you should open a new window/application instance.

Licenses

• The Native Kernel is published under GPLv2
• The Managed Kernel is published under LGPLv3
• The Corelib is published under MIT
• The .NET Runtime is published under MIT