OSv is not a general purpose OS although it does support a subset of the Linux ABI for compatibility. Both application and OSv share the same address space and

OSv is not a general purpose OS although it does support a subset of the Linux ABI for compatibility. Both application and OSv share the same address space and application code is linked directly to the kernel at start-up (there's an embedded ELF linker). The design is wildly different from MirageOS but I don't really see why you would not call it an unikernel.