diff --git a/docker-compose.dev.yml b/docker-compose.dev.yml
index d40619c..21b1c22 100644
--- a/docker-compose.dev.yml
+++ b/docker-compose.dev.yml
@@ -2,15 +2,27 @@ version: '3.8'
 
 services:
   db:
-    image: postgres:latest
+    image: postgres:16-alpine
     environment:
-      POSTGRES_DB: your_database
-      POSTGRES_USER: your_user
-      POSTGRES_PASSWORD: your_password
+      POSTGRES_DB: rosetta_db
+      POSTGRES_USER: rosetta_user
+      POSTGRES_PASSWORD: rosetta_password
     ports:
       - "5432:5432"
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U rosetta_user"]
+      interval: 10s
+      timeout: 5s
+      retries: 5
 
   adminer:
     image: adminer
     ports:
-      - "8080:8080"
\ No newline at end of file
+      - "8080:8080"
+    depends_on:
+      - db
+
+volumes:
+  postgres_data:
\ No newline at end of file
diff --git a/pom.xml b/pom.xml
index 19b9e3e..c84b6a0 100644
--- a/pom.xml
+++ b/pom.xml
@@ -16,13 +16,31 @@
 
 
     <dependencies>
-    
-
         <dependency>
             <groupId>org.java-websocket</groupId>
             <artifactId>Java-WebSocket</artifactId>
             <version>1.6.0</version>
         </dependency>
 
+        <!-- Hibernate ORM -->
+        <dependency>
+            <groupId>org.hibernate.orm</groupId>
+            <artifactId>hibernate-core</artifactId>
+            <version>6.4.0.Final</version>
+        </dependency>
+
+        <!-- PostgreSQL JDBC Driver -->
+        <dependency>
+            <groupId>org.postgresql</groupId>
+            <artifactId>postgresql</artifactId>
+            <version>42.7.1</version>
+        </dependency>
+
+        <!-- Jakarta Persistence API -->
+        <dependency>
+            <groupId>jakarta.persistence</groupId>
+            <artifactId>jakarta.persistence-api</artifactId>
+            <version>3.1.0</version>
+        </dependency>
     </dependencies>
 </project>
\ No newline at end of file
diff --git a/src/main/java/com/rosetta/im/database/BaseEntity.java b/src/main/java/com/rosetta/im/database/BaseEntity.java
new file mode 100644
index 0000000..bb11391
--- /dev/null
+++ b/src/main/java/com/rosetta/im/database/BaseEntity.java
@@ -0,0 +1,29 @@
+package com.rosetta.im.database;
+
+public class BaseEntity {
+
+    /**
+     * Сохраняет сущность в базе данных.
+     * @param entity Сущность для сохранения.
+     */
+    public void save(Object entity) {
+        DatabaseManager.save(entity);
+    } 
+
+    /**
+     * Обновляет сущность в базе данных.
+     * @param entity Сущность для обновления.
+     */
+    public void update(Object entity) {
+        DatabaseManager.update(entity);
+    }
+
+    /**
+     * Удаляет сущность из базы данных.
+     * @param entity Сущность для удаления.
+     */
+    public void delete(Object entity) {
+        DatabaseManager.delete(entity);
+    }
+
+}
diff --git a/src/main/java/com/rosetta/im/database/DatabaseManager.java b/src/main/java/com/rosetta/im/database/DatabaseManager.java
new file mode 100644
index 0000000..62029b7
--- /dev/null
+++ b/src/main/java/com/rosetta/im/database/DatabaseManager.java
@@ -0,0 +1,80 @@
+package com.rosetta.im.database;
+
+import org.hibernate.Session;
+import org.hibernate.Transaction;
+
+import java.util.List;
+
+public class DatabaseManager {
+
+    public static <T> T save(T entity) {
+        Session session = HibernateUtil.openSession();
+        Transaction transaction = null;
+        try {
+            transaction = session.beginTransaction();
+            session.persist(entity);
+            transaction.commit();
+            return entity;
+        } catch (Exception e) {
+            if (transaction != null) {
+                transaction.rollback();
+            }
+            throw new RuntimeException("Error saving entity: " + e.getMessage(), e);
+        } finally {
+            session.close();
+        }
+    }
+
+    public static <T> T update(T entity) {
+        Session session = HibernateUtil.openSession();
+        Transaction transaction = null;
+        try {
+            transaction = session.beginTransaction();
+            session.merge(entity);
+            transaction.commit();
+            return entity;
+        } catch (Exception e) {
+            if (transaction != null) {
+                transaction.rollback();
+            }
+            throw new RuntimeException("Error updating entity: " + e.getMessage(), e);
+        } finally {
+            session.close();
+        }
+    }
+
+    public static <T> T findById(Class<T> entityClass, Long id) {
+        Session session = HibernateUtil.openSession();
+        try {
+            return session.find(entityClass, id);
+        } finally {
+            session.close();
+        }
+    }
+
+    public static <T> List<T> findAll(Class<T> entityClass) {
+        Session session = HibernateUtil.openSession();
+        try {
+            return session.createQuery("FROM " + entityClass.getSimpleName(), entityClass).list();
+        } finally {
+            session.close();
+        }
+    }
+
+    public static <T> void delete(T entity) {
+        Session session = HibernateUtil.openSession();
+        Transaction transaction = null;
+        try {
+            transaction = session.beginTransaction();
+            session.remove(entity);
+            transaction.commit();
+        } catch (Exception e) {
+            if (transaction != null) {
+                transaction.rollback();
+            }
+            throw new RuntimeException("Error deleting entity: " + e.getMessage(), e);
+        } finally {
+            session.close();
+        }
+    }
+}
diff --git a/src/main/java/com/rosetta/im/database/HibernateUtil.java b/src/main/java/com/rosetta/im/database/HibernateUtil.java
new file mode 100644
index 0000000..a1596de
--- /dev/null
+++ b/src/main/java/com/rosetta/im/database/HibernateUtil.java
@@ -0,0 +1,33 @@
+package com.rosetta.im.database;
+
+import org.hibernate.Session;
+import org.hibernate.SessionFactory;
+import org.hibernate.cfg.Configuration;
+
+public class HibernateUtil {
+    private static final SessionFactory sessionFactory;
+
+    static {
+        try {
+            sessionFactory = new Configuration().configure().buildSessionFactory();
+        } catch (Exception e) {
+            throw new ExceptionInInitializerError("Error initializing Hibernate: " + e.getMessage());
+        }
+    }
+
+    public static SessionFactory getSessionFactory() {
+        return sessionFactory;
+    }
+
+    public static Session getCurrentSession() {
+        return sessionFactory.getCurrentSession();
+    }
+
+    public static Session openSession() {
+        return sessionFactory.openSession();
+    }
+
+    public static void shutdown() {
+        sessionFactory.close();
+    }
+}
diff --git a/src/main/java/com/rosetta/im/database/converters/StringListConverter.java b/src/main/java/com/rosetta/im/database/converters/StringListConverter.java
new file mode 100644
index 0000000..6bd4d5b
--- /dev/null
+++ b/src/main/java/com/rosetta/im/database/converters/StringListConverter.java
@@ -0,0 +1,27 @@
+package com.rosetta.im.database.converters;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import jakarta.persistence.AttributeConverter;
+import jakarta.persistence.Converter;
+
+@Converter
+public class StringListConverter implements AttributeConverter<List<String>, String> {
+    @Override
+    public String convertToDatabaseColumn(List<String> attribute) {
+        if (attribute == null || attribute.isEmpty()) {
+            return "";
+        }
+        return String.join(",", attribute);
+    }
+
+    @Override
+    public List<String> convertToEntityAttribute(String dbData) {
+        if (dbData == null || dbData.isBlank()) {
+            return new ArrayList<>();
+        }
+        return new ArrayList<>(Arrays.asList(dbData.split(",")));
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/com/rosetta/im/database/entity/User.java b/src/main/java/com/rosetta/im/database/entity/User.java
new file mode 100644
index 0000000..e6d7a40
--- /dev/null
+++ b/src/main/java/com/rosetta/im/database/entity/User.java
@@ -0,0 +1,229 @@
+package com.rosetta.im.database.entity;
+
+import com.rosetta.im.database.BaseEntity;
+import com.rosetta.im.database.HibernateUtil;
+import com.rosetta.im.database.converters.StringListConverter;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Convert;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.Index;
+import jakarta.persistence.PrePersist;
+import jakarta.persistence.PreUpdate;
+import jakarta.persistence.Table;
+import org.hibernate.Session;
+import org.hibernate.Transaction;
+
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+
+@Entity
+@Table(name = "users", indexes = {
+		@Index(name = "idx_users_publickey", columnList = "publicKey", unique = true)
+})
+public class User extends BaseEntity {
+
+	@Id
+	@GeneratedValue(strategy = GenerationType.IDENTITY)
+	private Long id;
+
+	@Column(name = "privateKey", nullable = false)
+	private String privateKey;
+
+	@Column(name = "username")
+	private String username;
+
+	@Column(name = "title")
+	private String title;
+
+	@Column(name = "publicKey", nullable = false, unique = true)
+	private String publicKey;
+
+	@Column(name = "timestamp", nullable = false)
+	private long timestamp;
+
+	@Column(name = "createdTime", nullable = false, updatable = false)
+	private Date createdTime;
+
+	@Column(name = "verified", nullable = false)
+	private int verified;
+
+	@Convert(converter = StringListConverter.class)
+	@Column(name = "notificationsTokens", nullable = false)
+	private List<String> notificationsTokens = new ArrayList<>();
+
+	@PrePersist
+	protected void onCreate() {
+		createdTime = new Date();
+	}
+
+	@PreUpdate
+	protected void onUpdate() {
+		if (createdTime == null) {
+			createdTime = new Date();
+		}
+	}
+
+	public Long getId() {
+		return id;
+	}
+
+	public String getPrivateKey() {
+		return privateKey;
+	}
+
+	public void setPrivateKey(String privateKey) {
+		this.privateKey = privateKey;
+	}
+
+	public String getUsername() {
+		return username;
+	}
+
+	public void setUsername(String username) {
+		this.username = username;
+	}
+
+	public String getTitle() {
+		return title;
+	}
+
+	public void setTitle(String title) {
+		this.title = title;
+	}
+
+	public String getPublicKey() {
+		return publicKey;
+	}
+
+	public void setPublicKey(String publicKey) {
+		this.publicKey = publicKey;
+	}
+
+	public long getTimestamp() {
+		return timestamp;
+	}
+
+	public void setTimestamp(long timestamp) {
+		this.timestamp = timestamp;
+	}
+
+	public Date getCreatedTime() {
+		return createdTime;
+	}
+
+	public int getVerified() {
+		return verified;
+	}
+
+	public void setVerified(int verified) {
+		this.verified = verified;
+	}
+
+	public List<String> getNotificationsTokens() {
+		return notificationsTokens;
+	}
+
+	public void setNotificationsTokens(List<String> notificationsTokens) {
+		this.notificationsTokens = notificationsTokens;
+	}
+
+	public static User getByPrivateKey(String privateKey) {
+		try (Session session = HibernateUtil.openSession()) {
+			return session.createQuery(
+							"from User where privateKey = :privateKey", User.class)
+					.setParameter("privateKey", privateKey)
+					.uniqueResult();
+		}
+	}
+
+	public static User getByUsername(String username) {
+		try (Session session = HibernateUtil.openSession()) {
+			return session.createQuery(
+							"from User where username = :username", User.class)
+					.setParameter("username", username)
+					.uniqueResult();
+		}
+	}
+
+	public static User getByPublicKey(String publicKey) {
+		try (Session session = HibernateUtil.openSession()) {
+			return session.createQuery(
+							"from User where publicKey = :publicKey", User.class)
+					.setParameter("publicKey", publicKey)
+					.uniqueResult();
+		}
+	}
+
+	public static void addNotificationToken(String privateKey, String token) {
+		Session session = HibernateUtil.openSession();
+		Transaction transaction = null;
+		try {
+			transaction = session.beginTransaction();
+			User user = session.createQuery(
+							"from User where privateKey = :privateKey", User.class)
+					.setParameter("privateKey", privateKey)
+					.uniqueResult();
+			if (user != null) {
+				if (!user.notificationsTokens.contains(token)) {
+					user.notificationsTokens.add(token);
+					session.merge(user);
+				}
+			}
+			transaction.commit();
+		} catch (Exception e) {
+			if (transaction != null) {
+				transaction.rollback();
+			}
+			throw new RuntimeException("Error adding notification token: " + e.getMessage(), e);
+		} finally {
+			session.close();
+		}
+	}
+
+	public static void removeNotificationToken(String privateKey, String token) {
+		Session session = HibernateUtil.openSession();
+		Transaction transaction = null;
+		try {
+			transaction = session.beginTransaction();
+			User user = session.createQuery(
+							"from User where privateKey = :privateKey", User.class)
+					.setParameter("privateKey", privateKey)
+					.uniqueResult();
+			if (user != null) {
+				user.notificationsTokens = new ArrayList<>(user.notificationsTokens.stream()
+					.filter(t -> !t.equals(token))
+					.toList());
+				session.merge(user);
+			}
+			transaction.commit();
+		} catch (Exception e) {
+			if (transaction != null) {
+				transaction.rollback();
+			}
+			throw new RuntimeException("Error removing notification token: " + e.getMessage(), e);
+		} finally {
+			session.close();
+		}
+	}
+
+	public static List<String> getNotificationTokensByPrivateKey(String privateKey) {
+		User user = getByPrivateKey(privateKey);
+		if (user != null) {
+			return user.notificationsTokens;
+		}
+		return List.of();
+	}
+
+	public static List<String> getNotificationsTokensByPublicKey(String publicKey) {
+		User user = getByPublicKey(publicKey);
+		if (user != null) {
+			return user.notificationsTokens;
+		}
+		return List.of();
+	}
+}
diff --git a/src/main/resources/hibernate.cfg.xml b/src/main/resources/hibernate.cfg.xml
new file mode 100644
index 0000000..80bb79d
--- /dev/null
+++ b/src/main/resources/hibernate.cfg.xml
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.5//EN" "http://www.hibernate.org/dtd/hibernate-configuration-3.5.dtd">
+<hibernate-configuration>
+    <session-factory>
+        <property name="hibernate.connection.driver_class">org.postgresql.Driver</property>
+        <property name="hibernate.connection.url">jdbc:postgresql://localhost:5432/rosetta_db</property>
+        <property name="hibernate.connection.username">rosetta_user</property>
+        <property name="hibernate.connection.password">rosetta_password</property>
+        <property name="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</property>
+        <property name="hibernate.hbm2ddl.auto">update</property>
+        <property name="hibernate.show_sql">true</property>
+        <property name="hibernate.format_sql">true</property>
+        <!--Зарегистрированные таблицы-->
+        <mapping class="com.rosetta.im.database.entity.User"/>
+        
+    </session-factory>
+</hibernate-configuration>