diff --git a/lib/Migration/Version30Date20260410000000.php b/lib/Migration/Version30Date20260410000000.php
new file mode 100644
index 0000000..bb86db3
--- /dev/null
+++ b/lib/Migration/Version30Date20260410000000.php
@@ -0,0 +1,88 @@
+<?php
+
+declare(strict_types=1);
+
+// SPDX-FileCopyrightText: Chen Asraf <contact@casraf.dev>
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+namespace OCA\Forum\Migration;
+
+use Closure;
+use OCP\DB\ISchemaWrapper;
+use OCP\IDBConnection;
+use OCP\Migration\IOutput;
+use OCP\Migration\SimpleMigrationStep;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Version 30 Migration:
+ * Repair migration to ensure Version 29 columns exist.
+ * On some PostgreSQL instances, Version 29 may have failed silently,
+ * leaving parent_id and hide_children_on_card columns missing.
+ *
+ * The header_id nullable change is handled separately in postSchemaChange
+ * via raw SQL so that a failure there cannot block the new column additions.
+ */
+class Version30Date20260410000000 extends SimpleMigrationStep {
+	public function __construct(
+		private IDBConnection $db,
+		private LoggerInterface $logger,
+	) {
+	}
+
+	public function changeSchema(IOutput $output, Closure $schemaClosure, array $options): ?ISchemaWrapper {
+		/** @var ISchemaWrapper $schema */
+		$schema = $schemaClosure();
+
+		$changed = false;
+
+		if ($schema->hasTable('forum_categories')) {
+			$table = $schema->getTable('forum_categories');
+
+			if (!$table->hasColumn('parent_id')) {
+				$table->addColumn('parent_id', 'integer', [
+					'notnull' => false,
+					'unsigned' => true,
+					'default' => null,
+				]);
+				$table->addIndex(['parent_id'], 'forum_cat_parent_id_idx');
+				$changed = true;
+			}
+
+			if (!$table->hasColumn('hide_children_on_card')) {
+				$table->addColumn('hide_children_on_card', 'boolean', [
+					'notnull' => false,
+					'default' => false,
+				]);
+				$changed = true;
+			}
+		}
+
+		return $changed ? $schema : null;
+	}
+
+	public function postSchemaChange(IOutput $output, Closure $schemaClosure, array $options): void {
+		// Make header_id nullable via raw SQL so a failure here
+		// does not roll back the column additions above.
+		try {
+			$platform = $this->db->getDatabasePlatform();
+			$tableName = '*PREFIX*forum_categories';
+
+			if ($platform instanceof \Doctrine\DBAL\Platforms\PostgreSQLPlatform) {
+				$this->db->executeStatement(
+					'ALTER TABLE "' . $tableName . '" ALTER COLUMN "header_id" DROP NOT NULL'
+				);
+			} else {
+				// MySQL / MariaDB / SQLite
+				$this->db->executeStatement(
+					'ALTER TABLE `' . $tableName . '` MODIFY `header_id` INT DEFAULT NULL'
+				);
+			}
+		} catch (\Exception $e) {
+			// Non-fatal: header_id may already be nullable, or the ALTER may not be
+			// supported in this exact form. Category nesting (parentId) still works
+			// for new categories as long as the column additions succeeded.
+			$this->logger->warning('Version30: Could not make header_id nullable (may already be nullable): ' . $e->getMessage());
+		}
+	}
+}