diff --git a/.gitea/workflows/qs.yml b/.gitea/workflows/qs.yml
new file mode 100644
index 0000000..d1f7746
--- /dev/null
+++ b/.gitea/workflows/qs.yml
@@ -0,0 +1,50 @@
+name: "Quality Check"
+
+on:
+  - pull_request
+
+jobs:
+  test:
+    name: "Tests"
+    runs-on: "ubuntu-latest"
+    container:
+      image: "cimg/openjdk:21.0-node"
+    steps:
+      - name: "Checkout"
+        uses: actions/checkout@v3
+      - uses: actions/cache@v3
+        with:
+          path: |
+            ~/.gradle/caches
+            ~/.gradle/wrapper
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+          restore-keys: |
+            ${{ runner.os }}-gradle-
+      - name: "Prepare Gradle"
+        run: gradle clean
+      - name: "Check"
+        run: gradle testClasses
+      - name: "Stop Gradle"
+        run: gradle --stop
+  checkstyle:
+    name: "Checkstyle Main"
+    runs-on: "ubuntu-latest"
+    container:
+      image: "cimg/openjdk:21.0-node"
+    steps:
+      - name: "Checkout"
+        uses: actions/checkout@v3
+      - uses: actions/cache@v3
+        with:
+          path: |
+            ~/.gradle/caches
+            ~/.gradle/wrapper
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+          restore-keys: |
+            ${{ runner.os }}-gradle-
+      - name: "Prepare Gradle"
+        run: gradle clean
+      - name: "Check"
+        run: gradle check
+      - name: "Stop Gradle"
+        run: gradle --stop
diff --git a/build.gradle.kts b/build.gradle.kts
index 74fefa1..8aa3eba 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -2,14 +2,32 @@ plugins {
     java
     id("org.springframework.boot") version "3.3.4"
     id("io.spring.dependency-management") version "1.1.6"
+    id("checkstyle")
+}
+
+tasks.withType<Checkstyle> {
+    reports {
+        // Disable HTML report
+        html.required.set(false)
+
+        // Disable XML report
+        xml.required.set(false)
+    }
 }
 
 group = "de.szut"
 version = "0.0.1-SNAPSHOT"
 
+tasks.test {
+    useJUnitPlatform()
+
+    // Activate the 'test' profile for Spring during tests
+    systemProperty("spring.profiles.active", "test")
+}
+
 java {
     toolchain {
-        languageVersion = JavaLanguageVersion.of(22)
+        languageVersion = JavaLanguageVersion.of(21)
     }
 }
 
@@ -35,6 +53,7 @@ dependencies {
     implementation("org.springframework.boot:spring-boot-starter-oauth2-client:3.3.4")
     runtimeOnly("org.postgresql:postgresql")
     implementation("org.springdoc:springdoc-openapi-starter-webmvc-ui:2.6.0")
+    testImplementation("com.h2database:h2")
 }
 
 tasks.withType<Test> {
diff --git a/config/checkstyle/checkstyle-ignore.xml b/config/checkstyle/checkstyle-ignore.xml
new file mode 100644
index 0000000..fe3b2fe
--- /dev/null
+++ b/config/checkstyle/checkstyle-ignore.xml
@@ -0,0 +1,9 @@
+<?xml version="1.0"?>
+<!DOCTYPE suppressions PUBLIC
+        "-//Puppy Crawl//DTD Suppressions 1.2//EN"
+        "https://checkstyle.org/dtds/suppressions_1_2.dtd"
+        >
+
+<suppressions>
+    <suppress files="[\\/]de[\\/]hmmh[\\/]pmt[\\/]oas" checks="."/>
+</suppressions>
diff --git a/config/checkstyle/checkstyle.xml b/config/checkstyle/checkstyle.xml
new file mode 100644
index 0000000..d8f0701
--- /dev/null
+++ b/config/checkstyle/checkstyle.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0"?>
+<!DOCTYPE module PUBLIC
+        "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
+        "https://checkstyle.org/dtds/configuration_1_3.dtd"
+        >
+<module name="Checker">
+    <module name="SuppressionFilter">
+        <property name="file" value="${config_loc}/checkstyle-ignore.xml"/>
+    </module>
+
+    <property name="severity" value="error"/>
+    <property name="tabWidth" value="4"/>
+
+    <module name="LineLength">
+        <property name="max" value="500"/>
+    </module>
+    <module name="FileTabCharacter">
+        <property name="eachLine" value="true"/>
+    </module>
+
+    <module name="NewlineAtEndOfFile"/>
+
+</module>
diff --git a/src/main/java/de/szut/lf8_starter/config/OpenAPIConfiguration.java b/src/main/java/de/szut/lf8_starter/config/OpenAPIConfiguration.java
index 0501902..1b2282b 100644
--- a/src/main/java/de/szut/lf8_starter/config/OpenAPIConfiguration.java
+++ b/src/main/java/de/szut/lf8_starter/config/OpenAPIConfiguration.java
@@ -57,4 +57,4 @@ public class OpenAPIConfiguration {
     }
 
 
-}
\ No newline at end of file
+}
diff --git a/src/main/java/de/szut/lf8_starter/security/KeycloakLogoutHandler.java b/src/main/java/de/szut/lf8_starter/security/KeycloakLogoutHandler.java
index 3cc82f7..8555ef9 100644
--- a/src/main/java/de/szut/lf8_starter/security/KeycloakLogoutHandler.java
+++ b/src/main/java/de/szut/lf8_starter/security/KeycloakLogoutHandler.java
@@ -46,4 +46,4 @@ public class KeycloakLogoutHandler implements LogoutHandler {
         }
     }
 
-}
\ No newline at end of file
+}
diff --git a/src/main/java/de/szut/lf8_starter/security/KeycloakSecurityConfig.java b/src/main/java/de/szut/lf8_starter/security/KeycloakSecurityConfig.java
index d47d6ec..ea9e354 100644
--- a/src/main/java/de/szut/lf8_starter/security/KeycloakSecurityConfig.java
+++ b/src/main/java/de/szut/lf8_starter/security/KeycloakSecurityConfig.java
@@ -94,4 +94,4 @@ class KeycloakSecurityConfig {
         });
         return jwtAuthenticationConverter;
     }
-}
\ No newline at end of file
+}
diff --git a/src/main/resources/application-test.properties b/src/main/resources/application-test.properties
new file mode 100644
index 0000000..af21e0e
--- /dev/null
+++ b/src/main/resources/application-test.properties
@@ -0,0 +1,5 @@
+spring.datasource.url=jdbc:h2:mem:testdb;DB_CLOSE_DELAY=-1
+spring.datasource.driver-class-name=org.h2.Driver
+spring.datasource.username=sa
+spring.datasource.password=
+spring.jpa.database-platform=org.hibernate.dialect.H2Dialect
\ No newline at end of file
diff --git a/src/test/java/de/szut/lf8_starter/Lf8StarterApplicationTests.java b/src/test/java/de/szut/lf8_starter/Lf8StarterApplicationTests.java
index 942f2cb..b5c7f7b 100644
--- a/src/test/java/de/szut/lf8_starter/Lf8StarterApplicationTests.java
+++ b/src/test/java/de/szut/lf8_starter/Lf8StarterApplicationTests.java
@@ -2,6 +2,7 @@ package de.szut.lf8_starter;
 
 import org.junit.jupiter.api.Test;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.TestPropertySource;
 
 @SpringBootTest
 class Lf8StarterApplicationTests {