move stuff to parts dir

parts/ci.nix

@@ -0,0 +1,45 @@
+{
+  self,
+  inputs,
+  ...
+}: {
+  perSystem = {
+    lib,
+    pkgs,
+    system,
+    ...
+  }: {
+    packages = let
+      overlay = lib.fix (final: (import ../exprs/overlay.nix final pkgs));
+
+      # do not include a package if it's not available on the system or if it's broken
+      isValid = _: v:
+        lib.elem pkgs.system (v.meta.platforms or [pkgs.system]) && !(v.meta.broken or false);
+    in
+      lib.filterAttrs isValid overlay;
+  };
+
+  flake.ghaMatrix.include = let
+    inherit (inputs.nixpkgs) lib;
+
+    platforms = {
+      "x86_64-linux" = {
+        os = "ubuntu-latest";
+      };
+    };
+  in
+    lib.pipe platforms [
+      builtins.attrNames # get systems
+      (systems: lib.getAttrs systems self.packages) # get packages of each system
+      (lib.mapAttrs (_: builtins.attrNames)) # keep only the name of each package
+
+      # map each package in each system to an attrset
+      (lib.mapAttrsToList (system:
+        builtins.map (pkg: {
+          inherit (platforms.${system}) os;
+          pkg = "packages.${system}.${pkg}";
+        })))
+
+      lib.flatten
+    ];
+}