diff --git a/pkgs/development/libraries/vulkan-loader/default.nix b/pkgs/development/libraries/vulkan-loader/default.nix
index 163cea7565c0..068c1d3d2c2a 100644
--- a/pkgs/development/libraries/vulkan-loader/default.nix
+++ b/pkgs/development/libraries/vulkan-loader/default.nix
@@ -16,7 +16,7 @@ stdenv.mkDerivation rec {
 
   nativeBuildInputs = [ cmake pkg-config ];
   buildInputs = [ vulkan-headers ]
-    ++ lib.optionals (!stdenv.isDarwin) [ libX11 libxcb libXrandr wayland ];
+    ++ lib.optionals stdenv.isLinux [ libX11 libxcb libXrandr wayland ];
 
   cmakeFlags = [ "-DCMAKE_INSTALL_INCLUDEDIR=${vulkan-headers}/include" ]
     ++ lib.optional stdenv.isDarwin "-DSYSCONFDIR=${moltenvk}/share"
@@ -37,7 +37,7 @@ stdenv.mkDerivation rec {
   meta = with lib; {
     description = "LunarG Vulkan loader";
     homepage    = "https://www.lunarg.com";
-    platforms   = platforms.unix;
+    platforms   = platforms.unix ++ platforms.windows;
     license     = licenses.asl20;
     maintainers = [ maintainers.ralith ];
     broken = (version != vulkan-headers.version);
diff --git a/pkgs/development/tools/misc/pkg-config/default.nix b/pkgs/development/tools/misc/pkg-config/default.nix
index 5da91bccc120..663f3184b221 100644
--- a/pkgs/development/tools/misc/pkg-config/default.nix
+++ b/pkgs/development/tools/misc/pkg-config/default.nix
@@ -35,8 +35,12 @@ stdenv.mkDerivation rec {
          "ac_cv_func_posix_getgrgid_r=yes"
        ];
 
-  # Silence "incompatible integer to pointer conversion passing 'gsize'" when building with Clang.
-  env.NIX_CFLAGS_COMPILE = lib.optionalString stdenv.cc.isClang "-Wno-int-conversion";
+  env.NIX_CFLAGS_COMPILE = toString (
+    # Silence "incompatible integer to pointer conversion passing 'gsize'" when building with Clang.
+    lib.optionals stdenv.cc.isClang ["-Wno-int-conversion"]
+    # Silence fprintf format errors when building for Windows.
+    ++ lib.optionals stdenv.hostPlatform.isWindows ["-Wno-error=format"]
+  );
 
   enableParallelBuilding = true;
   doCheck = true;