Comment by Marsymars

Not really trickier, but different stack - we’re a .NET stack with a pile of linters, analyzers, tests, etc. No emulation, everything run natively on both x86-64 and ARM64. (But prior to actually running/debugging it on arm64, had various hang-ups.)

Native is also much faster than qemu emulation - I have a personal (non-.NET) project where I moved the CI from docker/qemu for x86+arm builds to separate x86+arm runners, and it cut the runtime from 10 minutes in total to 2 minutes per runner.