add created_at column to Subscription

subscription/migrations/0017_subscription_created_at.py

@@ -0,0 +1,47 @@
+# Generated by Django 5.2.17 on 2026-09-01 08:44
+from typing import TYPE_CHECKING
+
+import django.utils.timezone
+from django.db import migrations, models
+from django.db.migrations.state import StateApps
+from django.db.models import F, Min, Value
+from django.db.models.functions import Least
+from django.utils.timezone import now
+
+if TYPE_CHECKING:
+    import subscription.models
+
+
+def make_default_creation_date(apps: StateApps, schema_editor):
+    Subscription = apps.get_model("subscription", "Subscription")
+    Subscription.objects.update(
+        created_at=Least(
+            F("subscription_start"), Value(now()), output_field=models.DateTimeField()
+        )
+    )
+
+
+class Migration(migrations.Migration):
+    dependencies = [("subscription", "0016_alter_subscription_subscription_type")]
+
+    operations = [
+        migrations.AddField(
+            model_name="subscription",
+            name="created_at",
+            field=models.DateTimeField(
+                auto_now_add=True,
+                default=django.utils.timezone.now,
+                help_text=(
+                    "When this subscription was created. "
+                    "This date may differ from the start of the subscription."
+                ),
+                verbose_name="created_at",
+            ),
+            preserve_default=False,
+        ),
+        migrations.RunPython(
+            make_default_creation_date,
+            reverse_code=migrations.RunPython.noop,
+            elidable=True,
+        ),
+    ]

subscription/models.py

@@ -64,6 +64,14 @@ class Subscription(models.Model):
         max_length=20,
         verbose_name=_("location"),
     )
+    created_at = models.DateTimeField(
+        _("created_at"),
+        help_text=_(
+            "When this subscription was created. "
+            "This date may differ from the start of the subscription."
+        ),
+        auto_now_add=True,
+    )
 
     class Meta:
         ordering = ["subscription_start"]