diff --git a/module/CLI/src/Command/Tag/ListTagsCommand.php b/module/CLI/src/Command/Tag/ListTagsCommand.php
index eac0afd2..9b848d02 100644
--- a/module/CLI/src/Command/Tag/ListTagsCommand.php
+++ b/module/CLI/src/Command/Tag/ListTagsCommand.php
@@ -10,7 +10,7 @@ use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Output\OutputInterface;
 use Symfony\Component\Console\Style\SymfonyStyle;
 use Zend\I18n\Translator\TranslatorInterface;
-use function array_map;
+use function Functional\map;
 
 class ListTagsCommand extends Command
 {
@@ -45,15 +45,15 @@ class ListTagsCommand extends Command
         $io->table([$this->translator->translate('Name')], $this->getTagsRows());
     }
 
-    private function getTagsRows()
+    private function getTagsRows(): array
     {
         $tags = $this->tagService->listTags();
         if (empty($tags)) {
             return [[$this->translator->translate('No tags yet')]];
         }
 
-        return array_map(function (Tag $tag) {
+        return map($tags, function (Tag $tag) {
             return [(string) $tag];
-        }, $tags);
+        });
     }
 }
diff --git a/module/Core/src/Transformer/ShortUrlDataTransformer.php b/module/Core/src/Transformer/ShortUrlDataTransformer.php
index 04b992cc..0a7abe8c 100644
--- a/module/Core/src/Transformer/ShortUrlDataTransformer.php
+++ b/module/Core/src/Transformer/ShortUrlDataTransformer.php
@@ -5,9 +5,8 @@ namespace Shlinkio\Shlink\Core\Transformer;
 
 use Shlinkio\Shlink\Common\Rest\DataTransformerInterface;
 use Shlinkio\Shlink\Core\Entity\ShortUrl;
-use Shlinkio\Shlink\Core\Entity\Tag;
 use Shlinkio\Shlink\Core\Util\ShortUrlBuilderTrait;
-use function array_map;
+use function Functional\invoke;
 
 class ShortUrlDataTransformer implements DataTransformerInterface
 {
@@ -38,15 +37,10 @@ class ShortUrlDataTransformer implements DataTransformerInterface
             'longUrl' => $longUrl,
             'dateCreated' => $dateCreated !== null ? $dateCreated->toAtomString() : null,
             'visitsCount' => $value->getVisitsCount(),
-            'tags' => array_map([$this, 'serializeTag'], $value->getTags()->toArray()),
+            'tags' => invoke($value->getTags(), '__toString'),
 
             // Deprecated
             'originalUrl' => $longUrl,
         ];
     }
-
-    private function serializeTag(Tag $tag): string
-    {
-        return (string) $tag;
-    }
 }
diff --git a/module/Core/test/Exception/DeleteShortUrlExceptionTest.php b/module/Core/test/Exception/DeleteShortUrlExceptionTest.php
index 97f330ce..80c5ff10 100644
--- a/module/Core/test/Exception/DeleteShortUrlExceptionTest.php
+++ b/module/Core/test/Exception/DeleteShortUrlExceptionTest.php
@@ -5,7 +5,7 @@ namespace ShlinkioTest\Shlink\Core\Exception;
 
 use PHPUnit\Framework\TestCase;
 use Shlinkio\Shlink\Core\Exception\DeleteShortUrlException;
-use function array_map;
+use function Functional\map;
 use function range;
 
 class DeleteShortUrlExceptionTest extends TestCase
@@ -56,8 +56,8 @@ class DeleteShortUrlExceptionTest extends TestCase
 
     public function provideThresholds(): array
     {
-        return array_map(function (int $number) {
+        return map(range(5, 50, 5), function (int $number) {
             return [$number];
-        }, range(5, 50, 5));
+        });
     }
 }
diff --git a/module/Core/test/Service/ShortUrl/DeleteShortUrlServiceTest.php b/module/Core/test/Service/ShortUrl/DeleteShortUrlServiceTest.php
index 1094521e..db86a249 100644
--- a/module/Core/test/Service/ShortUrl/DeleteShortUrlServiceTest.php
+++ b/module/Core/test/Service/ShortUrl/DeleteShortUrlServiceTest.php
@@ -15,7 +15,7 @@ use Shlinkio\Shlink\Core\Model\Visitor;
 use Shlinkio\Shlink\Core\Options\DeleteShortUrlsOptions;
 use Shlinkio\Shlink\Core\Repository\ShortUrlRepositoryInterface;
 use Shlinkio\Shlink\Core\Service\ShortUrl\DeleteShortUrlService;
-use function array_map;
+use function Functional\map;
 use function range;
 
 class DeleteShortUrlServiceTest extends TestCase
@@ -32,9 +32,9 @@ class DeleteShortUrlServiceTest extends TestCase
     public function setUp()
     {
         $shortUrl = (new ShortUrl(''))->setShortCode('abc123')
-                                      ->setVisits(new ArrayCollection(array_map(function () {
+                                      ->setVisits(new ArrayCollection(map(range(0, 10), function () {
                                           return new Visit(new ShortUrl(''), Visitor::emptyInstance());
-                                      }, range(0, 10))));
+                                      })));
 
         $this->em = $this->prophesize(EntityManagerInterface::class);