diff --git a/src/modules/cards/application/services/ICardLibraryQueryService.ts b/src/modules/cards/application/services/ICardLibraryQueryService.ts
deleted file mode 100644
index 36917647..00000000
--- a/src/modules/cards/application/services/ICardLibraryQueryService.ts
+++ /dev/null
@@ -1,29 +0,0 @@
-import { Result } from '../../../../shared/core/Result';
-import { CardId } from '../../domain/value-objects/CardId';
-
-export interface ICardLibraryQueryService {
-  /**
-   * Get all user IDs who have this card in their library
-   */
-  getLibrariesForCard(cardId: CardId): Promise<Result<string[]>>;
-
-  /**
-   * Get all card IDs in a user's library
-   */
-  getCardsInLibrary(userId: string): Promise<Result<CardId[]>>;
-
-  /**
-   * Check if a specific card is in a user's library
-   */
-  isCardInLibrary(cardId: CardId, userId: string): Promise<Result<boolean>>;
-
-  /**
-   * Get library membership count for a card
-   */
-  getLibraryMembershipCount(cardId: CardId): Promise<Result<number>>;
-
-  /**
-   * Get total number of cards in a user's library
-   */
-  getLibraryCardCount(userId: string): Promise<Result<number>>;
-}
diff --git a/src/modules/cards/infrastructure/services/DrizzleCardLibraryQueryService.ts b/src/modules/cards/infrastructure/services/DrizzleCardLibraryQueryService.ts
deleted file mode 100644
index 499c26cb..00000000
--- a/src/modules/cards/infrastructure/services/DrizzleCardLibraryQueryService.ts
+++ /dev/null
@@ -1,95 +0,0 @@
-import { eq, and, count } from 'drizzle-orm';
-import { PostgresJsDatabase } from 'drizzle-orm/postgres-js';
-import { ICardLibraryQueryService } from '../../application/services/ICardLibraryQueryService';
-import { CardId } from '../../domain/value-objects/CardId';
-import { libraryMemberships } from '../repositories/schema/libraryMembership.sql';
-import { cards } from '../repositories/schema/card.sql';
-import { Result, ok, err } from '../../../../shared/core/Result';
-
-export class DrizzleCardLibraryQueryService
-  implements ICardLibraryQueryService
-{
-  constructor(private db: PostgresJsDatabase) {}
-
-  async getLibrariesForCard(cardId: CardId): Promise<Result<string[]>> {
-    try {
-      const results = await this.db
-        .select({ userId: libraryMemberships.userId })
-        .from(libraryMemberships)
-        .where(eq(libraryMemberships.cardId, cardId.getStringValue()));
-
-      return ok(results.map((r) => r.userId));
-    } catch (error) {
-      return err(error as Error);
-    }
-  }
-
-  async getCardsInLibrary(userId: string): Promise<Result<CardId[]>> {
-    try {
-      const results = await this.db
-        .select({ id: cards.id })
-        .from(cards)
-        .where(eq(cards.authorId, userId));
-
-      const cardIds: CardId[] = [];
-      for (const result of results) {
-        const cardIdResult = CardId.createFromString(result.id);
-        if (cardIdResult.isOk()) {
-          cardIds.push(cardIdResult.value);
-        }
-      }
-
-      return ok(cardIds);
-    } catch (error) {
-      return err(error as Error);
-    }
-  }
-
-  async isCardInLibrary(
-    cardId: CardId,
-    userId: string,
-  ): Promise<Result<boolean>> {
-    try {
-      const result = await this.db
-        .select({ id: cards.id })
-        .from(cards)
-        .where(
-          and(
-            eq(cards.id, cardId.getStringValue()),
-            eq(cards.authorId, userId),
-          ),
-        )
-        .limit(1);
-
-      return ok(result.length > 0);
-    } catch (error) {
-      return err(error as Error);
-    }
-  }
-
-  async getLibraryMembershipCount(cardId: CardId): Promise<Result<number>> {
-    try {
-      const results = await this.db
-        .select({ userId: libraryMemberships.userId })
-        .from(libraryMemberships)
-        .where(eq(libraryMemberships.cardId, cardId.getStringValue()));
-
-      return ok(results.length);
-    } catch (error) {
-      return err(error as Error);
-    }
-  }
-
-  async getLibraryCardCount(userId: string): Promise<Result<number>> {
-    try {
-      const result = await this.db
-        .select({ count: count() })
-        .from(cards)
-        .where(eq(cards.authorId, userId));
-
-      return ok(result[0]?.count || 0);
-    } catch (error) {
-      return err(error as Error);
-    }
-  }
-}