diff --git a/module/Core/config/dependencies.config.php b/module/Core/config/dependencies.config.php
index 7ae8ae27..ad3452e4 100644
--- a/module/Core/config/dependencies.config.php
+++ b/module/Core/config/dependencies.config.php
@@ -175,7 +175,10 @@ return [
             Visit\Repository\VisitDeleterRepository::class,
             ShortUrl\ShortUrlResolver::class,
         ],
-        ShortUrl\Helper\ShortCodeUniquenessHelper::class => ['em', Config\Options\UrlShortenerOptions::class],
+        ShortUrl\Helper\ShortCodeUniquenessHelper::class => [
+            ShortUrl\Repository\ShortUrlRepository::class,
+            Config\Options\UrlShortenerOptions::class,
+        ],
         Domain\DomainService::class => [
             'em',
             Config\Options\UrlShortenerOptions::class,
diff --git a/module/Core/src/ShortUrl/Helper/ShortCodeUniquenessHelper.php b/module/Core/src/ShortUrl/Helper/ShortCodeUniquenessHelper.php
index 7f863f6c..7c7f2a76 100644
--- a/module/Core/src/ShortUrl/Helper/ShortCodeUniquenessHelper.php
+++ b/module/Core/src/ShortUrl/Helper/ShortCodeUniquenessHelper.php
@@ -4,25 +4,21 @@ declare(strict_types=1);
 
 namespace Shlinkio\Shlink\Core\ShortUrl\Helper;
 
-use Doctrine\ORM\EntityManagerInterface;
 use Shlinkio\Shlink\Core\Config\Options\UrlShortenerOptions;
 use Shlinkio\Shlink\Core\ShortUrl\Entity\ShortUrl;
 use Shlinkio\Shlink\Core\ShortUrl\Model\ShortUrlIdentifier;
-use Shlinkio\Shlink\Core\ShortUrl\Repository\ShortUrlRepository;
+use Shlinkio\Shlink\Core\ShortUrl\Repository\ShortUrlRepositoryInterface;
 
-class ShortCodeUniquenessHelper implements ShortCodeUniquenessHelperInterface
+readonly class ShortCodeUniquenessHelper implements ShortCodeUniquenessHelperInterface
 {
-    public function __construct(
-        private readonly EntityManagerInterface $em,
-        private readonly UrlShortenerOptions $options,
-    ) {
+    public function __construct(private ShortUrlRepositoryInterface $repo, private UrlShortenerOptions $options)
+    {
     }
 
     public function ensureShortCodeUniqueness(ShortUrl $shortUrlToBeCreated, bool $hasCustomSlug): bool
     {
-        /** @var ShortUrlRepository $repo */
-        $repo = $this->em->getRepository(ShortUrl::class);
-        $otherShortUrlsExist = $repo->shortCodeIsInUseWithLock(ShortUrlIdentifier::fromShortUrl($shortUrlToBeCreated));
+        $identifier = ShortUrlIdentifier::fromShortUrl($shortUrlToBeCreated);
+        $otherShortUrlsExist = $this->repo->shortCodeIsInUseWithLock($identifier);
 
         if (! $otherShortUrlsExist) {
             return true;
diff --git a/module/Core/test/ShortUrl/Helper/ShortCodeUniquenessHelperTest.php b/module/Core/test/ShortUrl/Helper/ShortCodeUniquenessHelperTest.php
index f341585e..c08a95af 100644
--- a/module/Core/test/ShortUrl/Helper/ShortCodeUniquenessHelperTest.php
+++ b/module/Core/test/ShortUrl/Helper/ShortCodeUniquenessHelperTest.php
@@ -4,7 +4,6 @@ declare(strict_types=1);
 
 namespace ShlinkioTest\Shlink\Core\ShortUrl\Helper;
 
-use Doctrine\ORM\EntityManagerInterface;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Test;
 use PHPUnit\Framework\MockObject\MockObject;
@@ -14,18 +13,18 @@ use Shlinkio\Shlink\Core\Domain\Entity\Domain;
 use Shlinkio\Shlink\Core\ShortUrl\Entity\ShortUrl;
 use Shlinkio\Shlink\Core\ShortUrl\Helper\ShortCodeUniquenessHelper;
 use Shlinkio\Shlink\Core\ShortUrl\Model\ShortUrlIdentifier;
-use Shlinkio\Shlink\Core\ShortUrl\Repository\ShortUrlRepository;
+use Shlinkio\Shlink\Core\ShortUrl\Repository\ShortUrlRepositoryInterface;
 
 class ShortCodeUniquenessHelperTest extends TestCase
 {
     private ShortCodeUniquenessHelper $helper;
-    private MockObject & EntityManagerInterface $em;
+    private MockObject & ShortUrlRepositoryInterface $repo;
     private MockObject & ShortUrl $shortUrl;
 
     protected function setUp(): void
     {
-        $this->em = $this->createMock(EntityManagerInterface::class);
-        $this->helper = new ShortCodeUniquenessHelper($this->em, new UrlShortenerOptions());
+        $this->repo = $this->createMock(ShortUrlRepositoryInterface::class);
+        $this->helper = new ShortCodeUniquenessHelper($this->repo, new UrlShortenerOptions());
 
         $this->shortUrl = $this->createMock(ShortUrl::class);
         $this->shortUrl->method('getShortCode')->willReturn('abc123');
@@ -36,16 +35,12 @@ class ShortCodeUniquenessHelperTest extends TestCase
     {
         $callIndex = 0;
         $expectedCalls = 3;
-        $repo = $this->createMock(ShortUrlRepository::class);
-        $repo->expects($this->exactly($expectedCalls))->method('shortCodeIsInUseWithLock')->with(
+        $this->repo->expects($this->exactly($expectedCalls))->method('shortCodeIsInUseWithLock')->with(
             ShortUrlIdentifier::fromShortCodeAndDomain('abc123', $expectedAuthority),
         )->willReturnCallback(function () use (&$callIndex, $expectedCalls) {
             $callIndex++;
             return $callIndex < $expectedCalls;
         });
-        $this->em->expects($this->exactly($expectedCalls))->method('getRepository')->with(ShortUrl::class)->willReturn(
-            $repo,
-        );
         $this->shortUrl->method('getDomain')->willReturn($domain);
         $this->shortUrl->expects($this->exactly($expectedCalls - 1))->method('regenerateShortCode')->with();
 
@@ -63,11 +58,9 @@ class ShortCodeUniquenessHelperTest extends TestCase
     #[Test]
     public function inUseSlugReturnsError(): void
     {
-        $repo = $this->createMock(ShortUrlRepository::class);
-        $repo->expects($this->once())->method('shortCodeIsInUseWithLock')->with(
+        $this->repo->expects($this->once())->method('shortCodeIsInUseWithLock')->with(
             ShortUrlIdentifier::fromShortCodeAndDomain('abc123'),
         )->willReturn(true);
-        $this->em->expects($this->once())->method('getRepository')->with(ShortUrl::class)->willReturn($repo);
         $this->shortUrl->method('getDomain')->willReturn(null);
         $this->shortUrl->expects($this->never())->method('regenerateShortCode');