Use Actually Portable Executable which enables you to compile textbook C programs as unikernels that boot on bare metal, as well as execute natively on all the existing operating systems too (without needing a runtime or interpreter). We've been working hard to democratize ring0 privileges since spectre has made the performance costs of having an operating system too high: https://github.com/jart/cosmopolitan/issues/20#issuecomment-...
Much of the point of suggesting Mirage was to get away from C - my position is that the correctness costs of C's undefined behaviour (as implemented by real-world C compilers), limited testing support, poor dependency management and so on are too high.
One of my goals with Cosmopolitan is to attract developers who build high-level languages. MirageOS depends on OCaml which depends on C. We need a sturdy foundation at the lowest levels that can enable these visions by helping high-level environments be successful. Cosmopolitan can be that foundation. For example, the codebase has 192 test programs. Much focus has been placed on using the Undefined Behavior Sanitizer and Address Sanitizer to vet everything. My past experience was working on projects like TensorFlow and I started security initiatives like Operation Rosehub which together helped us have the highest performance software infrastructure that's safer too.
By runtime I meant to say external runtimes. Your cosmo binaries are statically don't depend on anything except stable kernel interfaces, when you run on mac/nt/linux/bsd. That means it doesn't need to link any .so files like the glibc runtime. Therefore you won't be impacted by things like linux distro versioning and incompatibilities.
