Update jujutsu config.

nix/configuration/roles/jujutsu/default.nix

@@ -15,11 +15,29 @@
       example = true;
       description = "Whether we want to install jujutsu.";
     };
+
+    jujutsu.config = lib.mkOption {
+      type = lib.types.nullOr lib.types.path;
+      default = null;
+      example = ./files/jujutsu_config_home.toml;
+      description = "A jujutsu config file.";
+    };
   };
 
-  config = lib.mkIf config.me.jujutsu.enable {
-    environment.systemPackages = with pkgs; [
-      jujutsu
-    ];
-  };
+  config = lib.mkIf config.me.jujutsu.enable (
+    lib.mkMerge [
+      {
+        environment.systemPackages = with pkgs; [
+          jujutsu
+        ];
+      }
+      (lib.mkIf (config.me.jujutsu.config != null) {
+        me.install.user.talexander.file = {
+          ".config/jj/config.toml" = {
+            source = config.me.jujutsu.config;
+          };
+        };
+      })
+    ]
+  );
 }