Build a proper release.nix

release.nix

@@ -1,11 +1,59 @@
 { nixpkgs ? ./nix
-, supportedSystems ? [ "x86_64-linux" "x86_64-darwin" ]
+, supportedSystems ? [ "x86_64-linux" "x86_64-darwin" "aarch64-linux" ]
 }:
 let
   pkgs = import nixpkgs {};
   inherit (pkgs) lib;
 
-  ofborgpkgs = lib.genAttrs supportedSystems (system:
-    (import ./default.nix { pkgs = import nixpkgs { inherit system; }; })
-  );
-in ofborgpkgs
+  # An attrset of borgpkgs per supportedSystem:
+  #
+  # {
+  #   "x86_64-linux" = ...
+  #   "x86_64-darwin" = ...
+  # }
+  borgpkgs-per-arch = builtins.foldl'
+    (collector: system:
+      collector // {
+        "${system}" = import ./. {
+          pkgs = import nixpkgs { inherit system; };
+        };
+      }
+    )
+    {} supportedSystems;
+
+  attrForSystem = system: attrpath:
+    if borgpkgs-per-arch ? "${system}"
+    then (
+      let
+        borgpkgs = borgpkgs-per-arch."${system}";
+      in if lib.hasAttrByPath attrpath borgpkgs
+        then lib.setAttrByPath
+          (attrpath ++ [system])
+          (lib.attrByPath attrpath "bogus" borgpkgs)
+        else throw "Failed to find ${toString attrpath} for ${system} in borgpkgs"
+    )
+    else throw "No such system ${system}";
+
+  attrsForAllSystems = path:
+    builtins.foldl'
+      (collector: system:
+        lib.recursiveUpdate collector (attrForSystem system path)
+      )
+      {}
+      supportedSystems;
+
+  merge = attrsets:
+    builtins.foldl'
+      (collector: set: lib.recursiveUpdate set collector)
+      {}
+      attrsets;
+
+  x8664LinuxOnly = path:
+     (attrForSystem "x86_64-linux" path);
+
+in merge [
+  (attrsForAllSystems [ "ofborg" "rs" ])
+
+  (x8664LinuxOnly [ "ofborg" "php" ])
+  (x8664LinuxOnly [ "ircbot" ])
+]