fix: Ensure that we have pkg-config in the build inputs

Author: notheotherben

flake.nix

@@ -34,16 +34,18 @@
           *.nix
           '' ./.;
 
-        nativeBuildInputs = [
-          pkgs.pkg-config
-        ]
+        nativeBuildInputs = []
         ++ lib.optionals stdenv.isDarwin [
           pkgs.libiconv
           pkgs.darwin.apple_sdk.frameworks.Security
           pkgs.darwin.apple_sdk.frameworks.SystemConfiguration
         ];
 
-        buildInputs = [ pkgs.openssl pkgs.protobuf ];
+        buildInputs = [
+          pkgs.pkg-config
+          pkgs.openssl
+          pkgs.protobuf
+        ];
 
         cargoArtifacts = craneLib.buildDepsOnly {
           inherit src nativeBuildInputs buildInputs;
@@ -71,6 +73,10 @@
             cargoClippyExtraArgs = "--all-targets --no-deps";
           };
 
+          grey-doc = craneLib.cargoDoc {
+            inherit cargoArtifacts src;
+          };
+
           # Check formatting
           grey-fmt = craneLib.cargoFmt {
             inherit src;