diff --git a/src/repositories/mysql-card-repository.ts b/src/repositories/mysql-card-repository.ts
new file mode 100644
index 0000000..8fb1498
--- /dev/null
+++ b/src/repositories/mysql-card-repository.ts
@@ -0,0 +1,123 @@
+import { createPool, type Pool, type ResultSetHeader, type RowDataPacket } from 'mysql2/promise'
+import type { Card, CardInput } from '../domain/card'
+import type { CardRepository } from '../domain/card-repository'
+
+interface CardRow extends RowDataPacket {
+  id: string
+  question: string
+  response: string
+  theme: string
+  tags: string | null
+  createdAt: Date
+  updatedAt: Date
+}
+
+const FIELDS = ['id', 'question', 'response', 'theme', 'tags', 'createdAt', 'updatedAt'] as const
+
+export class MysqlCardRepository implements CardRepository {
+  private readonly pool: Pool
+
+  constructor(pool?: Pool) {
+    this.pool =
+      pool ??
+      createPool({
+        host: process.env.MYSQL_HOST ?? 'localhost',
+        port: Number(process.env.MYSQL_PORT ?? 13306),
+        user: process.env.MYSQL_USER ?? 'flashcards',
+        password: process.env.MYSQL_PASSWORD ?? 'flashcards',
+        database: process.env.MYSQL_DATABASE ?? 'flashcards',
+      })
+  }
+
+  private mapRow(row: CardRow): Card {
+    return {
+      id: row.id,
+      question: row.question,
+      response: row.response,
+      theme: row.theme,
+      tags: row.tags ? JSON.parse(row.tags) : [],
+      createdAt: new Date(row.createdAt),
+      updatedAt: new Date(row.updatedAt),
+    }
+  }
+
+  async findAll(): Promise<Card[]> {
+    const [rows] = await this.pool.query<CardRow[]>(`SELECT ${FIELDS.join(', ')} FROM cards`)
+    return rows.map((row) => this.mapRow(row))
+  }
+
+  async findById(id: string): Promise<Card | null> {
+    const [rows] = await this.pool.query<CardRow[]>(`SELECT ${FIELDS.join(', ')} FROM cards WHERE id = ?`, [id])
+    return rows[0] ? this.mapRow(rows[0]) : null
+  }
+
+  async create(input: CardInput): Promise<Card> {
+    const id = crypto.randomUUID()
+    const now = new Date()
+    await this.pool.query(
+      `INSERT INTO cards (${FIELDS.join(', ')}) VALUES (?, ?, ?, ?, ?, ?, ?)`,
+      [id, input.question, input.response, input.theme, JSON.stringify(input.tags ?? []), now, now],
+    )
+    return {
+      id,
+      question: input.question,
+      response: input.response,
+      theme: input.theme,
+      tags: input.tags ?? [],
+      createdAt: now,
+      updatedAt: now,
+    }
+  }
+
+  async update(id: string, input: Partial<CardInput>): Promise<Card | null> {
+    const sets: string[] = []
+    const values: unknown[] = []
+    if (input.question !== undefined) {
+      sets.push('question = ?')
+      values.push(input.question)
+    }
+    if (input.response !== undefined) {
+      sets.push('response = ?')
+      values.push(input.response)
+    }
+    if (input.theme !== undefined) {
+      sets.push('theme = ?')
+      values.push(input.theme)
+    }
+    if (input.tags !== undefined) {
+      sets.push('tags = ?')
+      values.push(JSON.stringify(input.tags))
+    }
+    if (sets.length === 0) {
+      return this.findById(id)
+    }
+    sets.push('updatedAt = ?')
+    values.push(new Date())
+    values.push(id)
+    await this.pool.query(`UPDATE cards SET ${sets.join(', ')} WHERE id = ?`, values)
+    return this.findById(id)
+  }
+
+  async delete(id: string): Promise<boolean> {
+    const [result] = await this.pool.query<ResultSetHeader>('DELETE FROM cards WHERE id = ?', [id])
+    return result.affectedRows > 0
+  }
+
+  async findRandom(): Promise<Card | null> {
+    const [rows] = await this.pool.query<CardRow[]>(`SELECT ${FIELDS.join(', ')} FROM cards ORDER BY RAND() LIMIT 1`)
+    return rows[0] ? this.mapRow(rows[0]) : null
+  }
+
+  async findRandomByTheme(theme: string): Promise<Card | null> {
+    const [rows] = await this.pool.query<CardRow[]>(
+      `SELECT ${FIELDS.join(', ')} FROM cards WHERE theme = ? ORDER BY RAND() LIMIT 1`,
+      [theme],
+    )
+    return rows[0] ? this.mapRow(rows[0]) : null
+  }
+
+  async findThemes(): Promise<string[]> {
+    const [rows] = await this.pool.query<RowDataPacket[]>('SELECT DISTINCT theme FROM cards ORDER BY theme')
+    return rows.map((row) => row.theme as string)
+  }
+}
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