Cant find Xlib.h but its added to targetPkgs

Help
1

I am trying to build WPILib but it throws both of these errors fatal error: GL/gl.h: No such file or directory 67 | #include <GL/gl.h> and fatal error: X11/Xlib.h: No such file or directory 32 | #include <X11/Xlib.h> and this is my flake

{
  description = "A Nix-flake for building WPILib";

  inputs.nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";

  outputs = inputs:
    let
      supportedSystems = [ "x86_64-linux" "aarch64-linux" ];
      forEachSupportedSystem = f: inputs.nixpkgs.lib.genAttrs supportedSystems (system: f {
        pkgs = import inputs.nixpkgs { inherit system; };
      });
    in
    {
      devShells = forEachSupportedSystem ({ pkgs }: 
      let
        fhs = pkgs.buildFHSEnv.override
          {
           stdenv = pkgs.stdenv;
          }
          {
            name = "WPILibSHell";
            targetPkgs = pkgs: (with pkgs; [
              llvmPackages.libcxxClang
              libgcc
              gfortran
              temurin-bin
              xorg.libX11
              xorg.libXcursor
              xorg.libXrandr
              xorg.libXinerama
              xorg.libXi
              libGL
            ]);
            multiPkgs = pkgs: (with pkgs; [
              xorg.libX11
              xorg.libXcursor
              xorg.libXrandr
              xorg.libXinerama
              xorg.libXi
              libGL
            ]);
            buildInputs = with pkgs; [ 
              xorg.libX11
              xorg.libXcursor
              xorg.libXrandr
              xorg.libXinerama
              xorg.libXi
              libGL];
            hardeningDisable = [ "fortify" ];
          };
        
        in
        { 
          default = fhs.env;
        });
    };
}

when i was using mkShell instead of buildFHSEnv it worked with them in build inputs, however i ran into other issues that made me switch to a sandbox.