diff --git a/build.gradle.kts b/build.gradle.kts
index ecf5d553a..b3e8a37fb 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -15,13 +15,15 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 import com.bmuschko.gradle.docker.tasks.image.DockerBuildImage
 import com.github.jengelman.gradle.plugins.shadow.ShadowJavaPlugin
+import org.gradle.kotlin.dsl.provider.inClassPathMode
 import java.time.Duration
 
 plugins {
+    checkstyle
     `java-library`
     `maven-publish`
     `jacoco-report-aggregation`
@@ -109,11 +111,18 @@ allprojects {
         configFile = rootProject.file("resources/tx-checkstyle-config.xml")
         configDirectory.set(rootProject.file("resources"))
 
+        tasks.checkstyleMain {
+            this.source = project.sourceSets.getByName("main").allSource
+        }
+
+        tasks.checkstyleTest {
+            this.source = project.sourceSets.getByName("test").allSource
+        }
+
         //checkstyle violations are reported at the WARN level
         this.isShowViolations = System.getProperty("checkstyle.verbose", "true").toBoolean()
     }
 
-
     // publishing to OSSRH is handled by the build plugin, but publishing to GH packages
     // must be configured separately
     publishing {
@@ -144,8 +153,9 @@ subprojects {
         if (project.plugins.hasPlugin("com.github.johnrengelman.shadow") &&
                 file("${project.projectDir}/src/main/docker/Dockerfile").exists()
         ) {
+            val buildDir = project.layout.buildDirectory.get().asFile
 
-            val agentFile = project.buildDir.resolve("opentelemetry-javaagent.jar")
+            val agentFile = buildDir.resolve("opentelemetry-javaagent.jar")
             // create task to download the opentelemetry agent
             val openTelemetryAgentUrl = "https://github.com/open-telemetry/opentelemetry-java-instrumentation/releases/download/v1.32.0/opentelemetry-javaagent.jar"
             val downloadOtel = tasks.create("downloadOtel") {
@@ -155,7 +165,7 @@ subprojects {
                 }
                 // this task could be the first in the graph, so "build/" may not yet exist. Let's be defensive
                 doFirst {
-                    project.buildDir.mkdirs()
+                    buildDir.mkdirs()
                 }
                 // download the jar file
                 doLast {
@@ -173,7 +183,7 @@ subprojects {
             // this task copies some legal docs into the build folder, so we can easily copy them into the docker images
             val copyLegalDocs = tasks.create("copyLegalDocs", Copy::class) {
                 from(project.rootProject.projectDir)
-                into("${project.buildDir}/legal")
+                into("${buildDir}/legal")
                 include("SECURITY.md", "NOTICE.md", "DEPENDENCIES", "LICENSE")
                 dependsOn(tasks.named(ShadowJavaPlugin.SHADOW_JAR_TASK_NAME))
             }
diff --git a/edc-controlplane/build.gradle.kts b/edc-controlplane/build.gradle.kts
index 0eb12e33b..9e901172f 100644
--- a/edc-controlplane/build.gradle.kts
+++ b/edc-controlplane/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-controlplane/edc-controlplane-base/build.gradle.kts b/edc-controlplane/edc-controlplane-base/build.gradle.kts
index 85eead488..fd7a31c80 100644
--- a/edc-controlplane/edc-controlplane-base/build.gradle.kts
+++ b/edc-controlplane/edc-controlplane-base/build.gradle.kts
@@ -16,7 +16,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-controlplane/edc-controlplane-postgresql-azure-vault/build.gradle.kts b/edc-controlplane/edc-controlplane-postgresql-azure-vault/build.gradle.kts
index 7c69d28a2..78a4c2022 100644
--- a/edc-controlplane/edc-controlplane-postgresql-azure-vault/build.gradle.kts
+++ b/edc-controlplane/edc-controlplane-postgresql-azure-vault/build.gradle.kts
@@ -16,7 +16,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
 
diff --git a/edc-controlplane/edc-controlplane-postgresql-hashicorp-vault/build.gradle.kts b/edc-controlplane/edc-controlplane-postgresql-hashicorp-vault/build.gradle.kts
index 5295fafc7..8c8c7cefa 100644
--- a/edc-controlplane/edc-controlplane-postgresql-hashicorp-vault/build.gradle.kts
+++ b/edc-controlplane/edc-controlplane-postgresql-hashicorp-vault/build.gradle.kts
@@ -16,7 +16,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
 
diff --git a/edc-controlplane/edc-runtime-memory/build.gradle.kts b/edc-controlplane/edc-runtime-memory/build.gradle.kts
index 04c936024..c5491e8b3 100644
--- a/edc-controlplane/edc-runtime-memory/build.gradle.kts
+++ b/edc-controlplane/edc-runtime-memory/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-dataplane/build.gradle.kts b/edc-dataplane/build.gradle.kts
index dc5814dce..4389a99cf 100644
--- a/edc-dataplane/build.gradle.kts
+++ b/edc-dataplane/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-dataplane/edc-dataplane-azure-vault/build.gradle.kts b/edc-dataplane/edc-dataplane-azure-vault/build.gradle.kts
index 4159fc0eb..0172e73d0 100644
--- a/edc-dataplane/edc-dataplane-azure-vault/build.gradle.kts
+++ b/edc-dataplane/edc-dataplane-azure-vault/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-dataplane/edc-dataplane-base/build.gradle.kts b/edc-dataplane/edc-dataplane-base/build.gradle.kts
index bc6bac2e3..f7b498f74 100644
--- a/edc-dataplane/edc-dataplane-base/build.gradle.kts
+++ b/edc-dataplane/edc-dataplane-base/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 
 plugins {
diff --git a/edc-dataplane/edc-dataplane-hashicorp-vault/build.gradle.kts b/edc-dataplane/edc-dataplane-hashicorp-vault/build.gradle.kts
index 975956f36..63063b271 100644
--- a/edc-dataplane/edc-dataplane-hashicorp-vault/build.gradle.kts
+++ b/edc-dataplane/edc-dataplane-hashicorp-vault/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-extensions/bpn-validation/bpn-validation-core/build.gradle.kts b/edc-extensions/bpn-validation/bpn-validation-core/build.gradle.kts
index 2a4c7226f..463660342 100644
--- a/edc-extensions/bpn-validation/bpn-validation-core/build.gradle.kts
+++ b/edc-extensions/bpn-validation/bpn-validation-core/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-extensions/bpn-validation/bpn-validation-spi/build.gradle.kts b/edc-extensions/bpn-validation/bpn-validation-spi/build.gradle.kts
index af7a94ab8..a40e19ec3 100644
--- a/edc-extensions/bpn-validation/bpn-validation-spi/build.gradle.kts
+++ b/edc-extensions/bpn-validation/bpn-validation-spi/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-extensions/bpn-validation/build.gradle.kts b/edc-extensions/bpn-validation/build.gradle.kts
index 335f1cd16..f4d82e271 100644
--- a/edc-extensions/bpn-validation/build.gradle.kts
+++ b/edc-extensions/bpn-validation/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-extensions/bpn-validation/business-partner-store-sql/build.gradle.kts b/edc-extensions/bpn-validation/business-partner-store-sql/build.gradle.kts
index 0f0c87646..eba92d316 100644
--- a/edc-extensions/bpn-validation/business-partner-store-sql/build.gradle.kts
+++ b/edc-extensions/bpn-validation/business-partner-store-sql/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-extensions/build.gradle.kts b/edc-extensions/build.gradle.kts
index 475444229..d6b1be67f 100644
--- a/edc-extensions/build.gradle.kts
+++ b/edc-extensions/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `java-library`
diff --git a/edc-extensions/dataplane-selector-configuration/build.gradle.kts b/edc-extensions/dataplane-selector-configuration/build.gradle.kts
index 133bd88c3..185d46b59 100644
--- a/edc-extensions/dataplane-selector-configuration/build.gradle.kts
+++ b/edc-extensions/dataplane-selector-configuration/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `maven-publish`
diff --git a/edc-extensions/postgresql-migration/build.gradle.kts b/edc-extensions/postgresql-migration/build.gradle.kts
index 027679f1e..22f26a7c2 100644
--- a/edc-extensions/postgresql-migration/build.gradle.kts
+++ b/edc-extensions/postgresql-migration/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `maven-publish`
diff --git a/edc-extensions/provision-additional-headers/build.gradle.kts b/edc-extensions/provision-additional-headers/build.gradle.kts
index a15240789..7eccfd232 100644
--- a/edc-extensions/provision-additional-headers/build.gradle.kts
+++ b/edc-extensions/provision-additional-headers/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `maven-publish`
diff --git a/edc-extensions/ssi/jws2020-crypto-suite/build.gradle.kts b/edc-extensions/ssi/jws2020-crypto-suite/build.gradle.kts
index e64ad023a..25602c5de 100644
--- a/edc-extensions/ssi/jws2020-crypto-suite/build.gradle.kts
+++ b/edc-extensions/ssi/jws2020-crypto-suite/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 plugins {
     `java-library`
 }
diff --git a/edc-extensions/transferprocess-sftp-client/build.gradle.kts b/edc-extensions/transferprocess-sftp-client/build.gradle.kts
index a552c7e94..67501fb0d 100644
--- a/edc-extensions/transferprocess-sftp-client/build.gradle.kts
+++ b/edc-extensions/transferprocess-sftp-client/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `maven-publish`
diff --git a/edc-extensions/transferprocess-sftp-common/build.gradle.kts b/edc-extensions/transferprocess-sftp-common/build.gradle.kts
index e7afd6b5e..1448161c5 100644
--- a/edc-extensions/transferprocess-sftp-common/build.gradle.kts
+++ b/edc-extensions/transferprocess-sftp-common/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `maven-publish`
diff --git a/edc-extensions/transferprocess-sftp-provisioner/build.gradle.kts b/edc-extensions/transferprocess-sftp-provisioner/build.gradle.kts
index 86379217c..67b6aee63 100644
--- a/edc-extensions/transferprocess-sftp-provisioner/build.gradle.kts
+++ b/edc-extensions/transferprocess-sftp-provisioner/build.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 plugins {
     `maven-publish`
diff --git a/resources/tx-checkstyle-config.xml b/resources/tx-checkstyle-config.xml
index 0f6c4fdfe..5c2258ca4 100644
--- a/resources/tx-checkstyle-config.xml
+++ b/resources/tx-checkstyle-config.xml
@@ -18,10 +18,8 @@
 
 <module name="Checker">
     <property name="charset" value="UTF-8"/>
-
     <property name="severity" value="error"/>
 
-    <property name="fileExtensions" value="java, properties, xml"/>
     <!-- Excludes all 'module-info.java' files              -->
     <!-- See https://checkstyle.org/config_filefilters.html -->
     <module name="BeforeExecutionExclusionFileFilter">
diff --git a/settings.gradle.kts b/settings.gradle.kts
index 230dd6082..b6630d82e 100644
--- a/settings.gradle.kts
+++ b/settings.gradle.kts
@@ -15,7 +15,7 @@
  * under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
- */
+ ********************************************************************************/
 
 rootProject.name = "tractusx-edc"