diff --git a/app/Services/CollectionCleanupService.php b/app/Services/CollectionCleanupService.php
index 3914e22c5..86b80dd02 100644
--- a/app/Services/CollectionCleanupService.php
+++ b/app/Services/CollectionCleanupService.php
@@ -11,6 +11,8 @@ use Illuminate\Support\Str;
 
 class CollectionCleanupService
 {
+    private const MAX_SQL_ROWS_PER_STATEMENT = 500;
+
     /**
      * Maximum number of retries for a lock-related DB error before giving up.
      */
@@ -50,28 +52,27 @@ class CollectionCleanupService
                 ), true);
         }
 
-        // Batch-delete old collections using a safe id-subselect to avoid read-then-delete races.
-        // The DELETE here is single-table (no JOIN), so cross-table deadlocks
-        // are not a concern; the helper still gives us bounded retries with
-        // jittered backoff and re-throws non-lock errors instead of swallowing them.
+        // Batch-delete old collections using select-then-delete so we can
+        // explicitly remove parts/binaries/collections even when FK cascades
+        // are not present in the runtime schema.
         $cutoff = now()->subHours(Settings::settingValue('partretentionhours'));
         $batchDeleted = 0;
         do {
-            $affected = $this->retryOnLockError(
-                fn (): int => DB::affectingStatement(
-                    'DELETE FROM collections WHERE id IN (
-                        SELECT id FROM (
-                            SELECT id FROM collections WHERE dateadded < ? ORDER BY id LIMIT 500
-                        ) AS x
-                    )',
-                    [$cutoff]
-                ),
-                'Cleanup',
-                $echoCLI,
-            );
+            $ids = DB::table('collections')
+                ->where('dateadded', '<', $cutoff)
+                ->orderBy('id')
+                ->limit(self::MAX_SQL_ROWS_PER_STATEMENT)
+                ->pluck('id')
+                ->all();
+
+            if ($ids === []) {
+                break;
+            }
+
+            $affected = $this->deleteCollectionsAndDescendants($ids, 'Cleanup', $echoCLI);
 
             $batchDeleted += $affected;
-            if ($affected < 500) {
+            if ($affected < self::MAX_SQL_ROWS_PER_STATEMENT) {
                 break;
             }
             // Brief pause to reduce pressure on the lock manager in busy systems.
@@ -125,7 +126,7 @@ class CollectionCleanupService
         if ($echoCLI) {
             cli()->primary(
                 'Finished deleting '.$missedDeleted.' collections missed after NZB creation in '.($totalTime).Str::plural(' second', (int) $totalTime).
-                PHP_EOL.'Removed '.number_format($deletedCount).' parts/binaries/collection rows in '.$totalTime.Str::plural(' second', (int) $totalTime),
+                PHP_EOL.'Removed '.number_format($deletedCount).' collections (with related binaries/parts) in '.$totalTime.Str::plural(' second', (int) $totalTime),
                 true
             );
         }
@@ -146,7 +147,7 @@ class CollectionCleanupService
     {
         $deleted = 0;
         $maxBatches = 20; // hard cap per cycle; bounded backlog drain
-        $batchSize = 500;
+        $batchSize = self::MAX_SQL_ROWS_PER_STATEMENT;
 
         for ($i = 0; $i < $maxBatches; $i++) {
             $ids = DB::table('collections as c')
@@ -162,11 +163,7 @@ class CollectionCleanupService
                 break;
             }
 
-            $affected = $this->retryOnLockError(
-                fn (): int => DB::table('collections')->whereIn('id', $ids)->delete(),
-                'Orphan cleanup',
-                $echoCLI,
-            );
+            $affected = $this->deleteCollectionsAndDescendants($ids, 'Orphan cleanup', $echoCLI);
 
             $deleted += $affected;
             if ($affected < $batchSize) {
@@ -199,7 +196,7 @@ class CollectionCleanupService
     {
         $deleted = 0;
         $maxBatches = 20;
-        $batchSize = 500;
+        $batchSize = self::MAX_SQL_ROWS_PER_STATEMENT;
 
         for ($i = 0; $i < $maxBatches; $i++) {
             $ids = DB::table('collections as c')
@@ -214,11 +211,7 @@ class CollectionCleanupService
                 break;
             }
 
-            $affected = $this->retryOnLockError(
-                fn (): int => DB::table('collections')->whereIn('id', $ids)->delete(),
-                'Missed-NZB cleanup',
-                $echoCLI,
-            );
+            $affected = $this->deleteCollectionsAndDescendants($ids, 'Missed-NZB cleanup', $echoCLI);
 
             $deleted += $affected;
             if ($affected < $batchSize) {
@@ -230,6 +223,51 @@ class CollectionCleanupService
         return $deleted;
     }
 
+    /**
+     * Explicitly delete parts, binaries, then collections for the given IDs.
+     * This path does not rely on DB-level cascade constraints.
+     *
+     * @param  list<int>  $collectionIds
+     */
+    public function deleteCollectionsAndDescendants(
+        array $collectionIds,
+        string $label = 'CBP cleanup',
+        bool $echoCLI = false,
+    ): int {
+        if ($collectionIds === []) {
+            return 0;
+        }
+
+        $deletedCollections = 0;
+
+        foreach (array_chunk($collectionIds, self::MAX_SQL_ROWS_PER_STATEMENT) as $chunk) {
+            $placeholders = implode(',', array_fill(0, count($chunk), '?'));
+            $deletedCollections += $this->retryOnLockError(
+                fn (): int => DB::transaction(
+                    function () use ($chunk, $placeholders): int {
+                        DB::statement(
+                            "DELETE FROM parts WHERE binaries_id IN (SELECT id FROM binaries WHERE collections_id IN ({$placeholders}))",
+                            $chunk
+                        );
+                        DB::statement(
+                            "DELETE FROM binaries WHERE collections_id IN ({$placeholders})",
+                            $chunk
+                        );
+
+                        return (int) DB::affectingStatement(
+                            "DELETE FROM collections WHERE id IN ({$placeholders})",
+                            $chunk
+                        );
+                    }
+                ),
+                $label,
+                $echoCLI,
+            );
+        }
+
+        return $deletedCollections;
+    }
+
     /**
      * Run a DB write inside a bounded retry loop that only swallows transient
      * InnoDB lock errors (deadlock 1213, lock wait timeout 1205). Any other
diff --git a/app/Services/Nzb/NzbService.php b/app/Services/Nzb/NzbService.php
index 3471ae3fa..8689e1031 100644
--- a/app/Services/Nzb/NzbService.php
+++ b/app/Services/Nzb/NzbService.php
@@ -9,6 +9,7 @@ use App\Models\Collection;
 use App\Models\Part;
 use App\Models\Release;
 use App\Models\Settings;
+use App\Services\CollectionCleanupService;
 use Illuminate\Database\QueryException;
 use Illuminate\Support\Facades\DB;
 use Illuminate\Support\Facades\File;
@@ -57,8 +58,9 @@ class NzbService
 
     protected string $siteCommentString;
 
-    public function __construct()
-    {
+    public function __construct(
+        private readonly CollectionCleanupService $collectionCleanupService,
+    ) {
         try {
             $nzbSplitLevel = (int) Settings::settingValue('nzbsplitlevel');
         } catch (QueryException $e) {
@@ -217,9 +219,11 @@ class NzbService
         // Delete CBP (Collections, Binaries, Parts) for release that has its NZB created.
         // Use a transaction to ensure cascading deletes complete properly.
         try {
-            DB::transaction(function () use ($release) {
-                Collection::query()->where('releases_id', $release->id)->delete();
-            });
+            $this->collectionCleanupService->deleteCollectionsAndDescendants(
+                $collectionIds,
+                'NZB cleanup',
+                false
+            );
         } catch (\Throwable $e) {
             // Log the error but don't fail the NZB creation since the file was written successfully
             Log::warning('Failed to delete collections for release '.$release->id.': '.$e->getMessage());
diff --git a/app/Services/ReleaseCreationService.php b/app/Services/ReleaseCreationService.php
index 58dc3bf35..1c4c3a04a 100644
--- a/app/Services/ReleaseCreationService.php
+++ b/app/Services/ReleaseCreationService.php
@@ -21,7 +21,8 @@ use Illuminate\Support\Str;
 class ReleaseCreationService
 {
     public function __construct(
-        private readonly ReleaseCleaningService $releaseCleaning
+        private readonly ReleaseCleaningService $releaseCleaning,
+        private readonly CollectionCleanupService $collectionCleanupService,
     ) {}
 
     /**
@@ -171,9 +172,11 @@ class ReleaseCreationService
                     }
                 }
             } else {
-                DB::transaction(static function () use ($collection) {
-                    Collection::query()->where('collectionhash', $collection->collectionhash)->delete();
-                }, 10);
+                $this->collectionCleanupService->deleteCollectionsAndDescendants(
+                    [$collection->id],
+                    'Duplicate cleanup',
+                    $echoCLI
+                );
 
                 $duplicate++;
             }
diff --git a/app/Services/ReleaseProcessingService.php b/app/Services/ReleaseProcessingService.php
index 695814985..802df2f1a 100644
--- a/app/Services/ReleaseProcessingService.php
+++ b/app/Services/ReleaseProcessingService.php
@@ -85,11 +85,11 @@ final class ReleaseProcessingService
         $this->releaseCleaning = $releaseCleaning ?? new ReleaseCleaningService;
         $this->releaseManagement = $releaseManagement ?? app(ReleaseManagementService::class);
         $this->releaseImage = $releaseImage ?? new ReleaseImageService;
-
-        $this->releaseCreationService = $releaseCreationService
-            ?? new ReleaseCreationService($this->releaseCleaning);
         $this->collectionCleanupService = $collectionCleanupService
             ?? new CollectionCleanupService;
+
+        $this->releaseCreationService = $releaseCreationService
+            ?? new ReleaseCreationService($this->releaseCleaning, $this->collectionCleanupService);
         $this->postProcessService = $postProcessService;
 
         $this->settings = $this->loadSettings();
@@ -432,21 +432,22 @@ final class ReleaseProcessingService
         $stats = ['minSize' => 0, 'maxSize' => 0, 'minFiles' => 0, 'par2Only' => 0];
 
         // Delete collections where ALL binaries are par2 files (no actual content)
-        DB::transaction(static function () use (&$stats): void {
-            $par2OnlyCollectionIds = DB::table('collections as c')
-                ->join('binaries as b', 'c.id', '=', 'b.collections_id')
-                ->where('c.filecheck', CollectionFileCheckStatus::Sized->value)
-                ->where('c.filesize', '>', 0)
-                ->groupBy('c.id')
-                ->havingRaw("COUNT(b.id) = SUM(CASE WHEN b.name REGEXP '\\\\.(vol[0-9]+\\\\+[0-9]+\\\\.par2|par2)' THEN 1 ELSE 0 END)")
-                ->pluck('c.id');
+        $par2OnlyCollectionIds = DB::table('collections as c')
+            ->join('binaries as b', 'c.id', '=', 'b.collections_id')
+            ->where('c.filecheck', CollectionFileCheckStatus::Sized->value)
+            ->where('c.filesize', '>', 0)
+            ->groupBy('c.id')
+            ->havingRaw("COUNT(b.id) = SUM(CASE WHEN b.name REGEXP '\\\\.(vol[0-9]+\\\\+[0-9]+\\\\.par2|par2)' THEN 1 ELSE 0 END)")
+            ->pluck('c.id')
+            ->all();
 
-            if ($par2OnlyCollectionIds->isNotEmpty()) {
-                $stats['par2Only'] += Collection::query()
-                    ->whereIn('id', $par2OnlyCollectionIds)
-                    ->delete();
-            }
-        }, 10);
+        if ($par2OnlyCollectionIds !== []) {
+            $stats['par2Only'] += $this->collectionCleanupService->deleteCollectionsAndDescendants(
+                $par2OnlyCollectionIds,
+                'Par2-only cleanup',
+                $this->echoCLI
+            );
+        }
 
         foreach ($groupIDs as $grpID) {
             $groupSettings = UsenetGroup::getGroupByID($grpID['id']);
@@ -457,32 +458,48 @@ final class ReleaseProcessingService
                 continue;
             }
 
-            DB::transaction(function () use ($groupMinSize, $groupMinFiles, &$stats): void {
-                $effectiveMinSize = max($groupMinSize, $this->settings->minSizeToFormRelease);
-                if ($effectiveMinSize > 0) {
-                    $stats['minSize'] += Collection::query()
-                        ->where('filecheck', CollectionFileCheckStatus::Sized->value)
-                        ->where('filesize', '>', 0)
-                        ->where('filesize', '<', $effectiveMinSize)
-                        ->delete();
-                }
+            $effectiveMinSize = max($groupMinSize, $this->settings->minSizeToFormRelease);
+            if ($effectiveMinSize > 0) {
+                $ids = Collection::query()
+                    ->where('filecheck', CollectionFileCheckStatus::Sized->value)
+                    ->where('filesize', '>', 0)
+                    ->where('filesize', '<', $effectiveMinSize)
+                    ->pluck('id')
+                    ->all();
+                $stats['minSize'] += $this->collectionCleanupService->deleteCollectionsAndDescendants(
+                    $ids,
+                    'Min-size cleanup',
+                    $this->echoCLI
+                );
+            }
 
-                if ($this->settings->maxSizeToFormRelease > 0) {
-                    $stats['maxSize'] += Collection::query()
-                        ->where('filecheck', CollectionFileCheckStatus::Sized->value)
-                        ->where('filesize', '>', $this->settings->maxSizeToFormRelease)
-                        ->delete();
-                }
+            if ($this->settings->maxSizeToFormRelease > 0) {
+                $ids = Collection::query()
+                    ->where('filecheck', CollectionFileCheckStatus::Sized->value)
+                    ->where('filesize', '>', $this->settings->maxSizeToFormRelease)
+                    ->pluck('id')
+                    ->all();
+                $stats['maxSize'] += $this->collectionCleanupService->deleteCollectionsAndDescendants(
+                    $ids,
+                    'Max-size cleanup',
+                    $this->echoCLI
+                );
+            }
 
-                $effectiveMinFiles = max($groupMinFiles, $this->settings->minFilesToFormRelease);
-                if ($effectiveMinFiles > 0) {
-                    $stats['minFiles'] += Collection::query()
-                        ->where('filecheck', CollectionFileCheckStatus::Sized->value)
-                        ->where('filesize', '>', 0)
-                        ->where('totalfiles', '<', $effectiveMinFiles)
-                        ->delete();
-                }
-            }, 10);
+            $effectiveMinFiles = max($groupMinFiles, $this->settings->minFilesToFormRelease);
+            if ($effectiveMinFiles > 0) {
+                $ids = Collection::query()
+                    ->where('filecheck', CollectionFileCheckStatus::Sized->value)
+                    ->where('filesize', '>', 0)
+                    ->where('totalfiles', '<', $effectiveMinFiles)
+                    ->pluck('id')
+                    ->all();
+                $stats['minFiles'] += $this->collectionCleanupService->deleteCollectionsAndDescendants(
+                    $ids,
+                    'Min-files cleanup',
+                    $this->echoCLI
+                );
+            }
         }
 
         $this->outputCollectionDeleteStats($stats, $startTime);
@@ -993,20 +1010,24 @@ final class ReleaseProcessingService
 
         do {
             try {
-                $groupCondition = $groupID !== 0 ? 'AND groups_id = ? ' : '';
-                $batchLimit = self::BATCH_SIZE;
+                $query = DB::table('collections')
+                    ->where('added', '<', $cutoff)
+                    ->orderBy('id')
+                    ->limit(self::BATCH_SIZE);
+                if ($groupID !== 0) {
+                    $query->where('groups_id', '=', $groupID);
+                }
 
-                $sql = <<<SQL
-                    DELETE FROM collections WHERE id IN (
-                        SELECT id FROM (
-                            SELECT id FROM collections WHERE added < ? {$groupCondition}
-                            ORDER BY id LIMIT {$batchLimit}
-                        ) AS x
-                    )
-                SQL;
+                $ids = $query->pluck('id')->all();
+                if ($ids === []) {
+                    break;
+                }
 
-                $params = $groupID !== 0 ? [$cutoff, $groupID] : [$cutoff];
-                $affected = DB::affectingStatement($sql, $params);
+                $affected = $this->collectionCleanupService->deleteCollectionsAndDescendants(
+                    $ids,
+                    'Stuck collections cleanup',
+                    $this->echoCLI
+                );
                 break;
             } catch (Throwable $e) {
                 $attempt++;
diff --git a/database/migrations/2026_05_06_093900_restore_cbp_foreign_keys.php b/database/migrations/2026_05_06_093900_restore_cbp_foreign_keys.php
new file mode 100644
index 000000000..8df2e74ef
--- /dev/null
+++ b/database/migrations/2026_05_06_093900_restore_cbp_foreign_keys.php
@@ -0,0 +1,79 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        if (DB::getDriverName() === 'sqlite') {
+            return;
+        }
+
+        if (! Schema::hasTable('collections') || ! Schema::hasTable('binaries') || ! Schema::hasTable('parts')) {
+            return;
+        }
+
+        // Remove orphans so FK creation cannot fail on existing bad rows.
+        DB::statement(
+            'DELETE p FROM parts p LEFT JOIN binaries b ON b.id = p.binaries_id WHERE b.id IS NULL'
+        );
+        DB::statement(
+            'DELETE b FROM binaries b LEFT JOIN collections c ON c.id = b.collections_id WHERE c.id IS NULL'
+        );
+
+        $this->dropForeignKeyIfExists('parts', 'FK_binaries');
+        $this->dropForeignKeyIfExists('binaries', 'FK_Collections');
+
+        DB::statement(
+            'ALTER TABLE `binaries`
+                ADD CONSTRAINT `FK_Collections`
+                FOREIGN KEY (`collections_id`)
+                REFERENCES `collections` (`id`)
+                ON DELETE CASCADE
+                ON UPDATE CASCADE'
+        );
+
+        DB::statement(
+            'ALTER TABLE `parts`
+                ADD CONSTRAINT `FK_binaries`
+                FOREIGN KEY (`binaries_id`)
+                REFERENCES `binaries` (`id`)
+                ON DELETE CASCADE
+                ON UPDATE CASCADE'
+        );
+    }
+
+    public function down(): void
+    {
+        if (DB::getDriverName() === 'sqlite') {
+            return;
+        }
+
+        if (! Schema::hasTable('binaries') || ! Schema::hasTable('parts')) {
+            return;
+        }
+
+        $this->dropForeignKeyIfExists('parts', 'FK_binaries');
+        $this->dropForeignKeyIfExists('binaries', 'FK_Collections');
+    }
+
+    private function dropForeignKeyIfExists(string $table, string $constraintName): void
+    {
+        $exists = DB::select(
+            'SELECT CONSTRAINT_NAME
+             FROM information_schema.TABLE_CONSTRAINTS
+             WHERE CONSTRAINT_TYPE = "FOREIGN KEY"
+               AND TABLE_SCHEMA = DATABASE()
+               AND TABLE_NAME = ?
+               AND CONSTRAINT_NAME = ?',
+            [$table, $constraintName]
+        );
+
+        if ($exists !== []) {
+            DB::statement("ALTER TABLE `{$table}` DROP FOREIGN KEY `{$constraintName}`");
+        }
+    }
+};
diff --git a/tests/Feature/CbpCleanupServiceTest.php b/tests/Feature/CbpCleanupServiceTest.php
new file mode 100644
index 000000000..1521157db
--- /dev/null
+++ b/tests/Feature/CbpCleanupServiceTest.php
@@ -0,0 +1,283 @@
+<?php
+
+namespace Tests\Feature;
+
+use App\Enums\CollectionFileCheckStatus;
+use App\Models\Release;
+use App\Services\CollectionCleanupService;
+use App\Services\Nzb\NzbService;
+use App\Services\ReleaseCleaningService;
+use App\Services\ReleaseCreationService;
+use Illuminate\Support\Facades\DB;
+use Tests\TestCase;
+
+class CbpCleanupServiceTest extends TestCase
+{
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        config(['database.default' => 'sqlite', 'database.connections.sqlite.database' => ':memory:']);
+        DB::purge();
+        DB::reconnect();
+        DB::connection()->getPdo()->sqliteCreateFunction('UNIX_TIMESTAMP', static fn (?string $value): int => strtotime((string) $value));
+
+        $this->createTables();
+        $this->seedSettings();
+    }
+
+    public function test_retention_cleanup_deletes_parts_binaries_and_collections_without_fk_cascades(): void
+    {
+        DB::table('collections')->insert([
+            'id' => 100,
+            'subject' => 'Retention.Release',
+            'fromname' => 'poster@example.com',
+            'date' => now()->subHours(10)->format('Y-m-d H:i:s'),
+            'dateadded' => now()->subHours(10)->format('Y-m-d H:i:s'),
+            'added' => now()->subHours(10)->format('Y-m-d H:i:s'),
+            'xref' => 'alt.test:123',
+            'groups_id' => 1,
+            'totalfiles' => 1,
+            'filesize' => 500,
+            'filecheck' => CollectionFileCheckStatus::Sized->value,
+            'collectionhash' => 'retention-hash',
+            'collection_regexes_id' => 0,
+            'releases_id' => null,
+            'noise' => '',
+        ]);
+        DB::table('binaries')->insert([
+            'id' => 1000,
+            'name' => 'Retention.Release.par2',
+            'collections_id' => 100,
+            'totalparts' => 1,
+        ]);
+        DB::table('parts')->insert([
+            'binaries_id' => 1000,
+            'number' => 1,
+            'messageid' => '<retention-1@example.com>',
+            'partnumber' => 1,
+            'size' => 10,
+        ]);
+
+        app(CollectionCleanupService::class)->deleteFinishedAndOrphans(false);
+
+        $this->assertSame(0, DB::table('parts')->count());
+        $this->assertSame(0, DB::table('binaries')->count());
+        $this->assertSame(0, DB::table('collections')->count());
+    }
+
+    public function test_nzb_creation_cleans_up_collection_binary_and_parts_explicitly(): void
+    {
+        DB::table('releases')->insert([
+            'id' => 1,
+            'name' => 'Nzb.Release',
+            'searchname' => 'Nzb.Release',
+            'totalpart' => 1,
+            'groups_id' => 1,
+            'adddate' => now()->format('Y-m-d H:i:s'),
+            'guid' => str_repeat('a', 36),
+            'leftguid' => 'a',
+            'postdate' => now()->format('Y-m-d H:i:s'),
+            'fromname' => 'poster@example.com',
+            'size' => 500,
+            'passwordstatus' => 0,
+            'haspreview' => -1,
+            'categories_id' => 1,
+            'nfostatus' => -1,
+            'nzbstatus' => NzbService::NZB_NONE,
+            'isrenamed' => 1,
+            'iscategorized' => 1,
+            'predb_id' => 0,
+            'source' => null,
+            'nzb_guid' => null,
+        ]);
+
+        DB::table('collections')->insert([
+            'id' => 200,
+            'subject' => 'Nzb.Release',
+            'fromname' => 'poster@example.com',
+            'date' => now()->subHours(1)->format('Y-m-d H:i:s'),
+            'dateadded' => now()->subHours(1)->format('Y-m-d H:i:s'),
+            'added' => now()->subHours(1)->format('Y-m-d H:i:s'),
+            'xref' => 'alt.test:200',
+            'groups_id' => 1,
+            'totalfiles' => 1,
+            'filesize' => 500,
+            'filecheck' => CollectionFileCheckStatus::Inserted->value,
+            'collectionhash' => 'nzb-hash',
+            'collection_regexes_id' => 0,
+            'releases_id' => 1,
+            'noise' => '',
+        ]);
+        DB::table('binaries')->insert([
+            'id' => 2000,
+            'name' => 'Nzb.Release yEnc',
+            'collections_id' => 200,
+            'totalparts' => 1,
+        ]);
+        DB::table('parts')->insert([
+            'binaries_id' => 2000,
+            'number' => 1,
+            'messageid' => '<nzb-1@example.com>',
+            'partnumber' => 1,
+            'size' => 10,
+        ]);
+
+        $release = Release::query()->findOrFail(1);
+        $release->setRelation('category', (object) ['title' => 'Misc', 'parent' => (object) ['title' => 'Other']]);
+
+        $written = app(NzbService::class)->writeNzbForReleaseId($release);
+
+        $this->assertTrue($written);
+        $this->assertSame(0, DB::table('parts')->count());
+        $this->assertSame(0, DB::table('binaries')->count());
+        $this->assertSame(0, DB::table('collections')->count());
+        $this->assertSame(1, (int) DB::table('releases')->where('id', 1)->value('nzbstatus'));
+    }
+
+    public function test_duplicate_release_path_cleans_up_collection_binary_and_parts(): void
+    {
+        DB::table('releases')->insert([
+            'id' => 2,
+            'name' => 'Duplicate.Release',
+            'searchname' => 'Duplicate.Release',
+            'totalpart' => 1,
+            'groups_id' => 1,
+            'adddate' => now()->format('Y-m-d H:i:s'),
+            'guid' => str_repeat('b', 36),
+            'leftguid' => 'b',
+            'postdate' => now()->format('Y-m-d H:i:s'),
+            'fromname' => 'poster@example.com',
+            'size' => 1000,
+            'passwordstatus' => 0,
+            'haspreview' => -1,
+            'categories_id' => 1,
+            'nfostatus' => -1,
+            'nzbstatus' => NzbService::NZB_NONE,
+            'isrenamed' => 1,
+            'iscategorized' => 1,
+            'predb_id' => 0,
+            'source' => null,
+            'nzb_guid' => null,
+        ]);
+
+        DB::table('collections')->insert([
+            'id' => 300,
+            'subject' => 'Duplicate.Release',
+            'fromname' => 'poster@example.com',
+            'date' => now()->subHours(1)->format('Y-m-d H:i:s'),
+            'dateadded' => now()->subHours(1)->format('Y-m-d H:i:s'),
+            'added' => now()->subHours(1)->format('Y-m-d H:i:s'),
+            'xref' => 'alt.test:300',
+            'groups_id' => 1,
+            'totalfiles' => 1,
+            'filesize' => 1000,
+            'filecheck' => CollectionFileCheckStatus::Sized->value,
+            'collectionhash' => 'duplicate-hash',
+            'collection_regexes_id' => 0,
+            'releases_id' => null,
+            'noise' => '',
+        ]);
+        DB::table('binaries')->insert([
+            'id' => 3000,
+            'name' => 'Duplicate.Release yEnc',
+            'collections_id' => 300,
+            'totalparts' => 1,
+        ]);
+        DB::table('parts')->insert([
+            'binaries_id' => 3000,
+            'number' => 1,
+            'messageid' => '<duplicate-1@example.com>',
+            'partnumber' => 1,
+            'size' => 10,
+        ]);
+
+        $service = new ReleaseCreationService(
+            app(ReleaseCleaningService::class),
+            app(CollectionCleanupService::class)
+        );
+        $result = $service->createReleases(null, 10, false);
+
+        $this->assertSame(['added' => 0, 'dupes' => 1], $result);
+        $this->assertSame(0, DB::table('parts')->count());
+        $this->assertSame(0, DB::table('binaries')->count());
+        $this->assertSame(0, DB::table('collections')->count());
+    }
+
+    private function seedSettings(): void
+    {
+        $settings = [
+            'partretentionhours' => '1',
+            'nzbsplitlevel' => '1',
+            'check_passworded_rars' => '0',
+            'categorizeforeign' => '1',
+            'catwebdl' => '1',
+        ];
+
+        foreach ($settings as $name => $value) {
+            DB::table('settings')->insert(['name' => $name, 'value' => $value]);
+        }
+    }
+
+    private function createTables(): void
+    {
+        DB::statement('CREATE TABLE settings (name VARCHAR(255) PRIMARY KEY, value TEXT)');
+        DB::statement('CREATE TABLE usenet_groups (id INTEGER PRIMARY KEY, name VARCHAR(255))');
+        DB::statement('CREATE TABLE categories (id INTEGER PRIMARY KEY, title VARCHAR(255), parent_categories_id INTEGER NULL)');
+        DB::statement('CREATE TABLE releases (
+            id INTEGER PRIMARY KEY,
+            name VARCHAR(255),
+            searchname VARCHAR(255),
+            totalpart INTEGER,
+            groups_id INTEGER,
+            adddate DATETIME NULL,
+            guid VARCHAR(64),
+            leftguid VARCHAR(1),
+            postdate DATETIME NULL,
+            fromname VARCHAR(255),
+            size INTEGER,
+            passwordstatus INTEGER,
+            haspreview INTEGER,
+            categories_id INTEGER,
+            nfostatus INTEGER,
+            nzbstatus INTEGER,
+            isrenamed INTEGER,
+            iscategorized INTEGER,
+            predb_id INTEGER,
+            source VARCHAR(255) NULL,
+            nzb_guid BLOB NULL
+        )');
+        DB::statement('CREATE TABLE collections (
+            id INTEGER PRIMARY KEY,
+            subject VARCHAR(255),
+            fromname VARCHAR(255),
+            date DATETIME NULL,
+            dateadded DATETIME NULL,
+            added DATETIME NULL,
+            xref TEXT,
+            groups_id INTEGER,
+            totalfiles INTEGER,
+            filesize INTEGER,
+            filecheck INTEGER,
+            collectionhash VARCHAR(255),
+            collection_regexes_id INTEGER,
+            releases_id INTEGER NULL,
+            noise VARCHAR(64)
+        )');
+        DB::statement('CREATE TABLE binaries (
+            id INTEGER PRIMARY KEY,
+            name VARCHAR(255),
+            collections_id INTEGER,
+            totalparts INTEGER
+        )');
+        DB::statement('CREATE TABLE parts (
+            binaries_id INTEGER,
+            number INTEGER,
+            messageid VARCHAR(255),
+            partnumber INTEGER,
+            size INTEGER
+        )');
+        DB::table('usenet_groups')->insert(['id' => 1, 'name' => 'alt.test']);
+        DB::table('categories')->insert(['id' => 1, 'title' => 'Misc', 'parent_categories_id' => null]);
+    }
+}