attempt at arm64 building

.gitea/workflows/check-flake.yaml

@@ -17,12 +17,21 @@ jobs:
           extra_nix_config: |
             trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= s0.koi-bebop.ts.net:OjbzD86YjyJZpCp9RWaQKANaflcpKhtzBMNP8I2aPUU=
             substituters = https://cache.nixos.org/ http://s0.koi-bebop.ts.net:5000
+            sandbox-paths = /run/binfmt/arm=/usr/bin/qemu-aarch64-static
+            extra-platforms = aarch64-linux
 
       - name: Checkout the repository
         uses: actions/checkout@v3
         with:
           fetch-depth: 0
 
+      - name: Install QEMU for ARM64 building
+        run: apt-get update -q -y && apt-get install -q -y qemu-system-aarch64 qemu-efi binfmt-support qemu-user-static
+
+      - run: |
+          echo $PATH
+          which qemu-aarch64-static
+
       - name: Check Flake
         run: |
           # Can only build x84_64 for now, so pick out those specifically