feat(shell.nix): group linux only deps

shell.nix

@@ -16,72 +16,67 @@ with {
 with (pkgs);
 
 let
-  darwin-frameworks =
-    if isMacOS then
-      with pkgs.darwin.apple_sdk.frameworks; [
-        AppKit
-        CoreFoundation
-        CoreServices
-        CoreVideo
-        Foundation
-        Metal
-        Security
-      ]
-    else
-      [ ];
+  darwin-frameworks = if isMacOS then
+    with pkgs.darwin.apple_sdk.frameworks; [
+      AppKit
+      CoreFoundation
+      CoreServices
+      CoreVideo
+      Foundation
+      Metal
+      Security
+    ]
+  else
+    [ ];
+
+  linux-only = if !isMacOS then [
+    vulkan-headers
+    vulkan-loader
+    vulkan-tools
+    vulkan-validation-layers
+    xorg.libX11
+    xorg.libXcursor
+    xorg.libXrandr
+    xorg.libXi
+  ] else
+    [ ];
+
   llvmPkg = pkgs.llvm_10;
   lldPkg = pkgs.lld_10; # this should match llvm's version
   clangPkg = pkgs.clang_10; # this should match llvm's version
   zig = import ./nix/zig.nix { inherit pkgs isMacOS; };
-  inputs =
-    [
-      # build libraries
-      rustc
-      cargo
-      clippy
-      rustfmt
-      cmake
-      git
-      python3
-      llvmPkg
-      clangPkg
-      valgrind
-      pkg-config
-      zig
-      # llb deps
-      libffi
-      libxml2
-      xorg.libX11
-      zlib
-      vulkan-headers
-      vulkan-loader
-      vulkan-tools
-      vulkan-validation-layers
-      # faster builds - see https://github.com/rtfeldman/roc/blob/trunk/BUILDING_FROM_SOURCE.md#use-lld-for-the-linker
-      lldPkg
-      # dev tools
-      rust-analyzer
-      # (import ./nix/zls.nix { inherit pkgs zig; })
-      ccls
-    ];
+  inputs = [
+    # build libraries
+    rustc
+    cargo
+    clippy
+    rustfmt
+    cmake
+    git
+    python3
+    llvmPkg
+    clangPkg
+    valgrind
+    pkg-config
+    zig
+    # llb deps
+    libffi
+    libxml2
+    zlib
+    # faster builds - see https://github.com/rtfeldman/roc/blob/trunk/BUILDING_FROM_SOURCE.md#use-lld-for-the-linker
+    lldPkg
+    # dev tools
+    rust-analyzer
+    # (import ./nix/zls.nix { inherit pkgs zig; })
+    ccls
+  ];
+
 in mkShell {
-  buildInputs = inputs ++ darwin-frameworks;
+  buildInputs = inputs ++ darwin-frameworks ++ linux-only;
   LLVM_SYS_100_PREFIX = "${llvmPkg}";
 
-  APPEND_LIBRARY_PATH = stdenv.lib.makeLibraryPath [
-      pkgconfig
-      vulkan-headers
-      vulkan-loader
-      vulkan-tools
-      vulkan-validation-layers
-      xorg.libX11
-      xorg.libXcursor
-      xorg.libXrandr
-      xorg.libXi
-      libcxx
-      libcxxabi
-      libunwind
-    ];
+  APPEND_LIBRARY_PATH = stdenv.lib.makeLibraryPath
+    ([ pkgconfig libcxx libcxxabi libunwind ] ++ linux-only);
 
   # Aliases don't work cross shell, so we do this
   shellHook = ''