diff --git a/modules/home/helix.nix b/modules/home/helix.nix
index e2a54bc..465014b 100644
--- a/modules/home/helix.nix
+++ b/modules/home/helix.nix
@@ -124,19 +124,12 @@
           };
         };
 
-        languages.language = let
-          def = name: obj: {inherit name;} // obj;
-        in [
-          (def "git-commit" {
-            rulers = [73];
-          })
-          (def "jjdescription" {
-            rulers = [73];
-          })
-          (def "sql" {
+        languages.language = [
+          {
+            name = "sql";
             indent.tab-width = 4;
             indent.unit = "    ";
-          })
+          }
         ];
       };
     };
diff --git a/modules/home/jujutsu/default.nix b/modules/home/jujutsu/default.nix
index f0575a5..6f30618 100644
--- a/modules/home/jujutsu/default.nix
+++ b/modules/home/jujutsu/default.nix
@@ -198,6 +198,21 @@
           })
         ];
       }
+      (lib.mkIf config.modules.home.helix.enable {
+        # `jjdescription` is the jj commit-description filetype; `git-commit`
+        # belongs to git, which this module enables alongside jj. Both
+        # cap the summary line at the conventional 72 characters.
+        programs.helix.languages.language = [
+          {
+            name = "git-commit";
+            rulers = [73];
+          }
+          {
+            name = "jjdescription";
+            rulers = [73];
+          }
+        ];
+      })
       (lib.mkIf config.modules.home.nushell.enable {
         modules.home.wsl-bridge.map = {
           "~/.config/jj/scripts/fork.nu" = {