ci: try not to build the kernel over and over again

Author: soopyc

.github/workflows/CI.yml

@@ -48,7 +48,7 @@ jobs:
         GC_DONT_GC: 1
       run: |
         for output in $(nix flake show --json | nix run nixpkgs#jq -- -r 'keys[]'); do
-          nix build .#$output
+          nix build .#$output --accept-flake-config
           if [ $(du -B1M result/iso/*.iso | cut -f1) -gt 2000 ]; then
             split -d result/iso/*.iso -b 2000M nixos-$output.iso.part-
           else

flake.nix

@@ -6,6 +6,12 @@
     nixos-hardware.url = "github:NixOS/nixos-hardware";
   };
 
+  nixConfig = {
+    extra-trusted-substituters = [ "https://cache.soopy.moe" ];
+    extra-substituters = [ "https://cache.soopy.moe" ];
+    extra-trusted-public-keys = [ "cache.soopy.moe-1:0RZVsQeR+GOh0VQI9rvnHz55nVXkFardDqfm4+afjPo=" ];
+  };
+
   outputs = { self, nixpkgs, nixos-hardware }:
   let
     system = "x86_64-linux";