Sorry for the lateness of my reply. I had some trouble setting up sbuild-qemu + timezones. The package built fine on arm64 with an sbuild-qemu created arm64 image, so thank you both for you advice there.
> Does the upstream _actually_ need oaknut, or would a normal assembler do? > (gcc or clang or tbb etc) I'm still learning about the low-level concepts so I don't know if this answers your question, but here is the relevant entry in the upstream application (Citra) log: * externals: Add oaksim submodule Used for emitting ARM64 assembly * common: Implement aarch64 ABI Utilize oaknut to implement a stack frame. Here is the relevant commit: ( https://github.com/citra-emu/citra/commit/e13735b6245af0dab111af3a1c16aefa6ee4db67 ) I would need to patch the externals/CMakeLists.txt or submit changes upstream in order to package Citra without oaknut, which is fine. I'd like it to be as close to a vanilla tarball as possible if I can, though. David