dustbowl: install posy's cursors

nixos/dustbowl.nix

@@ -205,6 +205,8 @@
     element-desktop
     virt-manager
     zotero
+
+    (callPackage ./posy-cursor-black.nix { })
   ];
 
   # Use doas instead of sudo
@@ -346,7 +348,7 @@
   # Sway
   programs.sway = {
     extraSessionCommands = ''
-      export XCURSOR_THEME=Adwaita
+      export XCURSOR_THEME=posy-cursor-black
       export _JAVA_AWT_WM_NONREPARENTING=1
     '';
     wrapperFeatures.gtk = true;

nixos/posy-cursor-black.nix

@@ -0,0 +1,21 @@
+{ lib, stdenv, fetchFromGitHub }:
+
+stdenv.mkDerivation {
+  pname = "posy-cursor-black";
+  version = "unstable-2022-09-14";
+
+  src = fetchFromGitHub {
+    owner = "simtrami";
+    repo = "posy-improved-cursor-linux";
+    rev = "8c39b915bbba4717a450ef750fa8b0c0b60cb160";
+    sha256 = "i0N/QB5uzqHapMCDl6h6PWPJ4GOAyB1ds9qlqmZacLY=";
+  };
+
+  patches = [ ./posy-cursors-rename.patch ];
+
+  installPhase = ''
+    mkdir -p $out/share/icons/posy-cursor-black
+    cp Posy_Cursor_Black/index.theme $out/share/icons/posy-cursor-black/index.theme
+    cp -r Posy_Cursor_Black/cursors $out/share/icons/posy-cursor-black/cursors
+  '';
+}

nixos/posy-cursors-rename.patch

@@ -0,0 +1,11 @@
+diff --git a/Posy_Cursor_Black/index.theme b/Posy_Cursor_Black/index.theme
+index a16dda6..88f0584 100644
+--- a/Posy_Cursor_Black/index.theme
++++ b/Posy_Cursor_Black/index.theme
+@@ -1,4 +1,5 @@
+ [Icon Theme]
+-Name=Posy's Cursor Black
++Name=posy-cursor-black
+ Comment=Posy's improved cursors, black set.
++Inherits=hicolor
+ Example=left_ptr