Cross-language interoperation is normally a matter of agreeing on a boundary: a foreign function interface, a generated shim, a marshalling layer, or a shared intermediate representation. We describe a system in which no boundary exists. Subsets of C++ and of Rust are each lowered to plain C source, and one C compiler consumes the result, so a Rust function calling a C++ method is a C function calling a C function — same translation unit, same intermediate representation, same register allocator. The two lowerings are chosen to converge on identical symbols, with the consequence that a Rust impl Drop and a C++ destructor over the same data emit the same function, and a C++ class may hold a Rust value by value without a shim, a wrapper, or an annotation.Removing the boundary between the languages exposes a second one, below them: the artifact is C, but a C compiler, an assembler, a linker and a runtime still stand between C and a running program, and conventionally those are separate projects. We report a stack in which they are not. The whole path — two source languages to C, C to machine code, machine code to a static ELF executable — is roughly fifty thousand lines in one repository, with no external compiler, assembler, linker or C library involved.