diff --git a/requirements.txt b/requirements.txt
index 5fc05ca..d9901ad 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -9,6 +9,7 @@ django-extensions==4.1
 python-dateutil==2.9.0.post0
 pytz==2025.2
 git+https://github.com/python-social-auth/social-app-django.git@1225f4fadb5e88f54711cc111931054d5de985c7
+social-auth-core<6.0.0
 html5lib==1.1
 cached-property==2.0.1
 requests-oauthlib==2.0.0
diff --git a/store/migrations/0024_alter_batch_id_alter_tool_id_edit_idx_batch_ts.py b/store/migrations/0024_alter_batch_id_alter_tool_id_edit_idx_batch_ts.py
new file mode 100644
index 0000000..d392295
--- /dev/null
+++ b/store/migrations/0024_alter_batch_id_alter_tool_id_edit_idx_batch_ts.py
@@ -0,0 +1,27 @@
+# Generated by Django 5.1.7 on 2026-10-07 13:01
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('store', '0023_edits_bigints'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='batch',
+            name='id',
+            field=models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID'),
+        ),
+        migrations.AlterField(
+            model_name='tool',
+            name='id',
+            field=models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID'),
+        ),
+        migrations.AddIndex(
+            model_name='edit',
+            index=models.Index(fields=['batch', 'timestamp'], name='idx_batch_ts'),
+        ),
+    ]
diff --git a/store/models.py b/store/models.py
index 42d9aa6..2fb8038 100644
--- a/store/models.py
+++ b/store/models.py
@@ -307,7 +307,8 @@ class Edit(models.Model):
 
     class Meta:
         indexes = [
-            models.Index(fields=['batch', 'newrevid'])
+            models.Index(fields=['batch', 'newrevid']),
+            models.Index(fields=['batch', 'timestamp'], name='idx_batch_ts') # introduced by https://phabricator.wikimedia.org/T438504
         ]
 
     reverted_re = re.compile(r'^/\* undo:0\|\|(\d+)\|')