Add buildWithCargo as a thin wrapper around mkDerivation

flake.nix

@@ -19,8 +19,12 @@
           inherit system;
         };
 
+        myPkgs = myPkgsFor pkgs;
+
+        # To override do: lib.overrideScope' (self: super: { ... });
         lib = import ./lib {
           inherit (pkgs) lib newScope;
+          inherit myPkgs;
         };
 
         checks = pkgs.callPackages ./checks { };
@@ -28,7 +32,7 @@
       {
         inherit checks lib;
 
-        packages = myPkgsFor pkgs;
+        packages = myPkgs;
 
         devShell = pkgs.mkShell {
           inputsFrom = builtins.attrValues checks;

lib/buildWithCargo.nix

@@ -0,0 +1,21 @@
+{ cargo
+, configureCargoVendoredDepsHook
+, lib
+, stdenv
+}:
+
+args@{ nativeBuildInputs ? [ ], ... }:
+stdenv.mkDerivation (args // {
+  nativeBuildInputs = nativeBuildInputs ++ [
+    cargo
+    configureCargoVendoredDepsHook
+  ];
+
+  buildPhase = ''
+    cargo check --release
+  '';
+
+  installPhase = ''
+    touch $out
+  '';
+})

lib/default.nix

@@ -1,4 +1,5 @@
 { lib
+, myPkgs
 , newScope
 }:
 
@@ -6,9 +7,10 @@ lib.makeScope newScope (self:
   let
     callPackage = self.newScope { };
   in
-  {
+  myPkgs // {
     inherit callPackage;
 
+    buildWithCargo = callPackage ./buildWithCargo.nix { };
     downloadCargoPackage = callPackage ./downloadCargoPackage.nix { };
     urlForCargoPackage = callPackage ./urlForCargoPackage.nix { };
     vendorCargoDeps = callPackage ./vendorCargoDeps.nix { };

pkgs/configureCargoVendoredDepsHook.sh

@@ -14,5 +14,7 @@ EOF
 }
 
 if [ -n "${cargoVendorDir-}" ]; then
-  postPatchHooks+=(configureCargoVendoredDepsHook)
+  preConfigureHooks+=(configureCargoVendoredDepsHook)
+else
+  echo "cargoVendorDir not set"
 fi