diff --git a/src/Domain/Manga/Application/CommandHandler/FetchMangaChaptersHandler.php b/src/Domain/Manga/Application/CommandHandler/FetchMangaChaptersHandler.php
index f97847a..7149cba 100644
--- a/src/Domain/Manga/Application/CommandHandler/FetchMangaChaptersHandler.php
+++ b/src/Domain/Manga/Application/CommandHandler/FetchMangaChaptersHandler.php
@@ -52,20 +52,20 @@ readonly class FetchMangaChaptersHandler
                 // Définir les règles de priorité des langues (fr > en > autres)
                 $shouldReplaceChapter = false;
 
-                if (!isset($chaptersByNumber[$chapterNumber])) {
+                if (!isset($chaptersByNumber[(string) $chapterNumber])) {
                     // Si c'est le premier chapitre avec ce numéro qu'on rencontre
                     $shouldReplaceChapter = true;
                     $chapterNumbers[] = $chapterNumber;
                 } else if ($language === 'fr') {
                     // Le français est toujours prioritaire
                     $shouldReplaceChapter = true;
-                } else if ($language === 'en' && $chapterLanguages[$chapterNumber] !== 'fr') {
+                } else if ($language === 'en' && $chapterLanguages[(string) $chapterNumber] !== 'fr') {
                     // L'anglais est prioritaire sur les autres langues, sauf le français
                     $shouldReplaceChapter = true;
                 }
 
                 if ($shouldReplaceChapter) {
-                    $chaptersByNumber[$chapterNumber] = new Chapter(
+                    $chaptersByNumber[(string) $chapterNumber] = new Chapter(
                         new ChapterId((string) Uuid::uuid4()),
                         $manga->getId()->getValue(),
                         $chapterNumber,
@@ -75,7 +75,7 @@ readonly class FetchMangaChaptersHandler
                         false,
                         new \DateTimeImmutable()
                     );
-                    $chapterLanguages[$chapterNumber] = $language;
+                    $chapterLanguages[(string) $chapterNumber] = $language;
                 }
             }
 
@@ -94,7 +94,7 @@ readonly class FetchMangaChaptersHandler
 
         // Sauvegarde uniquement les nouveaux chapitres
         foreach ($chaptersByNumber as $chapterNumber => $chapter) {
-            if (!isset($existingChapters[$chapterNumber])) {
+            if (!isset($existingChapters[(float) $chapterNumber])) {
                 $this->mangaRepository->saveChapter($chapter);
             }
         }
diff --git a/src/Domain/Manga/Domain/Contract/Repository/MangaRepositoryInterface.php b/src/Domain/Manga/Domain/Contract/Repository/MangaRepositoryInterface.php
index fc97771..6c1fea2 100644
--- a/src/Domain/Manga/Domain/Contract/Repository/MangaRepositoryInterface.php
+++ b/src/Domain/Manga/Domain/Contract/Repository/MangaRepositoryInterface.php
@@ -21,5 +21,9 @@ interface MangaRepositoryInterface
     public function findBySlug(MangaSlug $slug): ?Manga;
     public function search(string $query, int $page = 1, int $limit = 20): array;
     public function countSearch(string $query): int;
+    /**
+     * @param float[] $chapterNumbers
+     * @return array<float, Chapter>
+     */
     public function findExistingChaptersByNumbers(string $mangaId, array $chapterNumbers): array;
 }
diff --git a/src/Domain/Manga/Infrastructure/Persistence/LegacyMangaRepository.php b/src/Domain/Manga/Infrastructure/Persistence/LegacyMangaRepository.php
index 61e450e..af5342e 100644
--- a/src/Domain/Manga/Infrastructure/Persistence/LegacyMangaRepository.php
+++ b/src/Domain/Manga/Infrastructure/Persistence/LegacyMangaRepository.php
@@ -200,6 +200,10 @@ readonly class LegacyMangaRepository implements MangaRepositoryInterface
             ->getSingleScalarResult();
     }
 
+    /**
+     * @param float[] $chapterNumbers
+     * @return array<float, Chapter>
+     */
     public function findExistingChaptersByNumbers(string $mangaId, array $chapterNumbers): array
     {
         $queryBuilder = $this->entityManager->createQueryBuilder()
@@ -208,13 +212,13 @@ readonly class LegacyMangaRepository implements MangaRepositoryInterface
             ->where('c.manga = :mangaId')
             ->andWhere('c.number IN (:chapterNumbers)')
             ->setParameter('mangaId', $mangaId)
-            ->setParameter('chapterNumbers', $chapterNumbers);
+            ->setParameter('chapterNumbers', array_map('floatval', $chapterNumbers));
 
         $chapters = $queryBuilder->getQuery()->getResult();
 
         $chaptersByNumber = [];
         foreach ($chapters as $chapter) {
-            $chaptersByNumber[$chapter->getNumber()] = $this->toChapterDomain($chapter);
+            $chaptersByNumber[(float) $chapter->getNumber()] = $this->toChapterDomain($chapter);
         }
 
         return $chaptersByNumber;
diff --git a/src/Domain/Scraping/Application/CommandHandler/ScrapeChapterHandler.php b/src/Domain/Scraping/Application/CommandHandler/ScrapeChapterHandler.php
index bad3337..20f4357 100644
--- a/src/Domain/Scraping/Application/CommandHandler/ScrapeChapterHandler.php
+++ b/src/Domain/Scraping/Application/CommandHandler/ScrapeChapterHandler.php
@@ -11,6 +11,7 @@ use App\Domain\Scraping\Domain\Contract\Service\ImageDownloaderInterface;
 use App\Domain\Scraping\Domain\Contract\Service\ScraperInterface;
 use App\Domain\Scraping\Domain\Event\ChapterScraped;
 use App\Domain\Scraping\Domain\Event\ChapterScrapingFailed;
+use App\Domain\Scraping\Domain\Model\Chapter;
 use App\Domain\Scraping\Domain\Model\ScrapingJob;
 use App\Domain\Scraping\Domain\Model\Source;
 use App\Domain\Scraping\Domain\Model\ValueObject\CbzGenerationRequest;
@@ -41,6 +42,7 @@ readonly class ScrapeChapterHandler
         $job = null;
         try {
             // 1. Récupération du chapitre
+            /**@var Chapter $chapter */
             $chapter = $this->chapterRepository->getById($command->chapterId);
             if (!$chapter) {
                 throw new \InvalidArgumentException("Chapter not found with ID: {$command->chapterId}");
diff --git a/src/Domain/Scraping/Domain/Contract/Repository/ChapterRepositoryInterface.php b/src/Domain/Scraping/Domain/Contract/Repository/ChapterRepositoryInterface.php
index cfd0591..73947f7 100644
--- a/src/Domain/Scraping/Domain/Contract/Repository/ChapterRepositoryInterface.php
+++ b/src/Domain/Scraping/Domain/Contract/Repository/ChapterRepositoryInterface.php
@@ -7,6 +7,9 @@ use App\Domain\Scraping\Domain\Model\Chapter;
 interface ChapterRepositoryInterface
 {
     public function getById(string $id): ?Chapter;
-    public function getByMangaIdAndChapterNumber(string $mangaId, int $chapterNumber): Chapter;
+    /**
+     * @throws ChapterNotFoundException
+     */
+    public function getByMangaIdAndChapterNumber(string $mangaId, float $chapterNumber): Chapter;
     public function save(Chapter $chapter): void;
 }
diff --git a/src/Domain/Scraping/Domain/Model/Chapter.php b/src/Domain/Scraping/Domain/Model/Chapter.php
index 14199eb..bd854a3 100644
--- a/src/Domain/Scraping/Domain/Model/Chapter.php
+++ b/src/Domain/Scraping/Domain/Model/Chapter.php
@@ -7,8 +7,8 @@ class Chapter
     public function __construct(
         public readonly string $id,
         public readonly string $mangaId,
-        public readonly int $chapterNumber,
-        public readonly int $volumeNumber,
-        public ?string $cbzPath = null,
+        public readonly float $chapterNumber,
+        public readonly ?int $volumeNumber,
+        public ?string $cbzPath,
     ) {}
 }
diff --git a/src/Domain/Scraping/Infrastructure/Persistence/LegacyChapterRepository.php b/src/Domain/Scraping/Infrastructure/Persistence/LegacyChapterRepository.php
index 00c2f5e..97773b4 100644
--- a/src/Domain/Scraping/Infrastructure/Persistence/LegacyChapterRepository.php
+++ b/src/Domain/Scraping/Infrastructure/Persistence/LegacyChapterRepository.php
@@ -36,23 +36,23 @@ readonly class LegacyChapterRepository implements ChapterRepositoryInterface
     /**
      * @throws ChapterNotFoundException
      */
-    public function getByMangaIdAndChapterNumber(string $mangaId, int $chapterNumber): Chapter
+    public function getByMangaIdAndChapterNumber(string $mangaId, float $chapterNumber): Chapter
     {
-        $chapterEntity = $this->entityManager->getRepository(EntityChapter::class)->findOneBy([
+        $entity = $this->entityManager->getRepository(EntityChapter::class)->findOneBy([
             'manga' => $mangaId,
-            'number' => $chapterNumber,
+            'number' => $chapterNumber
         ]);
 
-        if (!$chapterEntity) {
+        if ($entity === null) {
             throw new ChapterNotFoundException();
         }
 
         return new Chapter(
-            id: $chapterEntity->getId(),
-            mangaId: $chapterEntity->getManga()->getId(),
-            chapterNumber: $chapterEntity->getNumber(),
-            volumeNumber: $chapterEntity->getVolume(),
-            cbzPath: $chapterEntity->getCbzPath(),
+            id: $entity->getId(),
+            mangaId: $entity->getManga()->getId(),
+            chapterNumber: $entity->getNumber(),
+            volumeNumber: $entity->getVolume(),
+            cbzPath: $entity->getCbzPath(),
         );
     }
 
diff --git a/tests/Domain/Scraping/Adapter/InMemoryChapterRepository.php b/tests/Domain/Scraping/Adapter/InMemoryChapterRepository.php
index cf91f74..b0ec0cb 100644
--- a/tests/Domain/Scraping/Adapter/InMemoryChapterRepository.php
+++ b/tests/Domain/Scraping/Adapter/InMemoryChapterRepository.php
@@ -4,6 +4,7 @@ namespace App\Tests\Domain\Scraping\Adapter;
 
 use App\Domain\Scraping\Domain\Contract\Repository\ChapterRepositoryInterface;
 use App\Domain\Scraping\Domain\Model\Chapter;
+use App\Domain\Scraping\Domain\Exception\ChapterNotFoundException;
 
 class InMemoryChapterRepository implements ChapterRepositoryInterface
 {
@@ -14,7 +15,7 @@ class InMemoryChapterRepository implements ChapterRepositoryInterface
         return $this->chapters[$id] ?? null;
     }
 
-    public function getByMangaIdAndChapterNumber(string $mangaId, int $chapterNumber): Chapter
+    public function getByMangaIdAndChapterNumber(string $mangaId, float $chapterNumber): Chapter
     {
         foreach ($this->chapters as $chapter) {
             if ($chapter->mangaId === $mangaId && $chapter->chapterNumber === $chapterNumber) {
@@ -22,7 +23,7 @@ class InMemoryChapterRepository implements ChapterRepositoryInterface
             }
         }
 
-        throw new \RuntimeException('Chapter not found');
+        throw new ChapterNotFoundException();
     }
 
     public function save(Chapter $chapter): void