Modify font defaults
diff --git a/src/system.nix b/src/system.nix
index ed858ef..e6a011d 100644
--- a/src/system.nix
+++ b/src/system.nix
@@ -310,9 +310,9 @@
 
     fontconfig = {
       defaultFonts = {
-        serif = [ "Ubuntu" ];
-        sansSerif = [ "Roboto" "Ubuntu" ];
-        monospace = [ "Ubuntu" ];  
+        serif = [ "Twitter Color Emoji" "Fira Code Symbol" "Roboto Slab" ];
+        sansSerif = [ "Twitter Color Emoji" "Fira Code Symbol" "Roboto" "Ubuntu" ];
+        monospace = [ "Twitter Color Emoji" "Fira Code Symbol" "Roboto Mono" "Ubuntu Mono" ];
       };
     };
   };