diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index 8b078d1e..3c4c2bf4 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -17,7 +17,7 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
-    - name: Set up JDK 17
+    - name: Set up JDK 21
       uses: actions/setup-java@v3
       with:
         java-version: 21
diff --git a/README.md b/README.md
index 47943d42..3f72d274 100644
--- a/README.md
+++ b/README.md
@@ -12,7 +12,7 @@
 </p>
 
 <h1 align="center">DynamiaTools</h1>
-DynamiaTools is a cutting-edge full-stack Java 17+ framework designed for building powerful enterprise web applications, harnessing the strength of Spring Boot 3 and the elegance of ZK 10. 
+DynamiaTools is a cutting-edge full-stack Java 21+ framework designed for building powerful enterprise web applications, harnessing the strength of Spring Boot 4 and the elegance of ZK 10. 
 
 
 ## With DynamiaTools you can
diff --git a/app/src/main/java/tools/dynamia/app/controllers/GlobalExceptionController.java b/app/src/main/java/tools/dynamia/app/controllers/GlobalExceptionController.java
index 3cb1d683..4fd6c88a 100644
--- a/app/src/main/java/tools/dynamia/app/controllers/GlobalExceptionController.java
+++ b/app/src/main/java/tools/dynamia/app/controllers/GlobalExceptionController.java
@@ -17,7 +17,6 @@
 package tools.dynamia.app.controllers;
 
 import jakarta.servlet.http.HttpServletRequest;
-import org.springframework.boot.web.servlet.error.ErrorController;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.ExceptionHandler;
@@ -36,14 +35,12 @@
  * <p>
  * Provides handlers for navigation errors, general exceptions, and error endpoints.
  * Returns appropriate views and error information for UI clients.
- * <p>
- * Implements {@link ErrorController} for integration with Spring Boot error handling.
  *
  * @author Mario A. Serrano Leones
  * @since 2023
  */
 @Controller
-public class GlobalExceptionController implements ErrorController {
+public class GlobalExceptionController {
 
     /**
      * Logger for error and exception handling.
diff --git a/app/src/test/java/tools/dynamia/app/crud/CrudTestConfiguration.java b/app/src/test/java/tools/dynamia/app/crud/CrudTestConfiguration.java
index bef78506..2a871450 100644
--- a/app/src/test/java/tools/dynamia/app/crud/CrudTestConfiguration.java
+++ b/app/src/test/java/tools/dynamia/app/crud/CrudTestConfiguration.java
@@ -1,7 +1,6 @@
 package tools.dynamia.app.crud;
 
 import jakarta.persistence.EntityManagerFactory;
-import org.springframework.boot.autoconfigure.domain.EntityScan;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.jdbc.datasource.DriverManagerDataSource;
@@ -20,7 +19,6 @@
 import javax.sql.DataSource;
 
 @Configuration
-@EntityScan(basePackageClasses = {CrudTestConfiguration.class})
 public class CrudTestConfiguration {
 
     @Bean
diff --git a/domain-jpa/src/main/java/tools/dynamia/domain/jpa/ModularPersistenceUnitManager.java b/domain-jpa/src/main/java/tools/dynamia/domain/jpa/ModularPersistenceUnitManager.java
index e1f5e7ca..e811e0c3 100644
--- a/domain-jpa/src/main/java/tools/dynamia/domain/jpa/ModularPersistenceUnitManager.java
+++ b/domain-jpa/src/main/java/tools/dynamia/domain/jpa/ModularPersistenceUnitManager.java
@@ -53,7 +53,7 @@ protected void postProcessPersistenceUnitInfo(MutablePersistenceUnitInfo pui) {
         // Invoke normal post processing
         super.postProcessPersistenceUnitInfo(pui);
 
-        PersistenceUnitInfo oldPui = getPersistenceUnitInfo(pui.getPersistenceUnitName());
+        MutablePersistenceUnitInfo oldPui = getPersistenceUnitInfo(pui.getPersistenceUnitName());
 
         if (oldPui != null) {
             postProcessPersistenceUnitInfo(pui, oldPui);
@@ -66,7 +66,7 @@ protected void postProcessPersistenceUnitInfo(MutablePersistenceUnitInfo pui) {
      * @param pui the pui
      * @param oldPui the old pui
      */
-    void postProcessPersistenceUnitInfo(MutablePersistenceUnitInfo pui, PersistenceUnitInfo oldPui) {
+    void postProcessPersistenceUnitInfo(MutablePersistenceUnitInfo pui, MutablePersistenceUnitInfo oldPui) {
 
         for (URL url : oldPui.getJarFileUrls()) {
 
diff --git a/pom.xml b/pom.xml
index 870304ff..829e2b2d 100644
--- a/pom.xml
+++ b/pom.xml
@@ -80,7 +80,7 @@
 
     <properties>
         <main.baseUri>${project.baseUri}</main.baseUri>
-        <springboot.version>3.5.8</springboot.version>
+        <springboot.version>4.0.0</springboot.version>
         <swagger.version>2.2.38</swagger.version>
         <mongodb.version>1</mongodb.version>