diff --git a/samples/backend-for-spa-client/samples-backend-for-spa-client.gradle b/samples/backend-for-spa-client/samples-backend-for-spa-client.gradle
index 3ac55ff9..46eeabb2 100644
--- a/samples/backend-for-spa-client/samples-backend-for-spa-client.gradle
+++ b/samples/backend-for-spa-client/samples-backend-for-spa-client.gradle
@@ -1,5 +1,5 @@
 plugins {
-	id "org.springframework.boot" version "3.2.2"
+	id "org.springframework.boot" version "4.0.0-SNAPSHOT"
 	id "io.spring.dependency-management" version "1.1.0"
 	id "java"
 }
@@ -18,7 +18,7 @@ repositories {
 }
 
 ext {
-	set("springCloudVersion", "2023.0.2")
+	set("springCloudVersion", "2025.1.0-SNAPSHOT")
 }
 
 dependencyManagement {
diff --git a/samples/default-authorizationserver/samples-default-authorizationserver.gradle b/samples/default-authorizationserver/samples-default-authorizationserver.gradle
index 74b5b52d..02b38821 100644
--- a/samples/default-authorizationserver/samples-default-authorizationserver.gradle
+++ b/samples/default-authorizationserver/samples-default-authorizationserver.gradle
@@ -1,5 +1,5 @@
 plugins {
-	id "org.springframework.boot" version "3.4.3"
+	id "org.springframework.boot" version "4.0.0-SNAPSHOT"
 	id "io.spring.dependency-management" version "1.1.0"
 	id "java"
 }
diff --git a/samples/demo-authorizationserver/samples-demo-authorizationserver.gradle b/samples/demo-authorizationserver/samples-demo-authorizationserver.gradle
index e973d5f3..86c212f9 100644
--- a/samples/demo-authorizationserver/samples-demo-authorizationserver.gradle
+++ b/samples/demo-authorizationserver/samples-demo-authorizationserver.gradle
@@ -1,5 +1,5 @@
 plugins {
-	id "org.springframework.boot" version "3.4.3"
+	id "org.springframework.boot" version "4.0.0-SNAPSHOT"
 	id "io.spring.dependency-management" version "1.1.0"
 	id "java"
 }
diff --git a/samples/demo-client/samples-demo-client.gradle b/samples/demo-client/samples-demo-client.gradle
index 6665c319..4c66be07 100644
--- a/samples/demo-client/samples-demo-client.gradle
+++ b/samples/demo-client/samples-demo-client.gradle
@@ -1,5 +1,5 @@
 plugins {
-	id "org.springframework.boot" version "3.2.2"
+	id "org.springframework.boot" version "4.0.0-SNAPSHOT"
 	id "io.spring.dependency-management" version "1.1.0"
 	id "java"
 }
diff --git a/samples/messages-resource/samples-messages-resource.gradle b/samples/messages-resource/samples-messages-resource.gradle
index f122bb50..46d95712 100644
--- a/samples/messages-resource/samples-messages-resource.gradle
+++ b/samples/messages-resource/samples-messages-resource.gradle
@@ -1,5 +1,5 @@
 plugins {
-	id "org.springframework.boot" version "3.2.2"
+	id "org.springframework.boot" version "4.0.0-SNAPSHOT"
 	id "io.spring.dependency-management" version "1.1.0"
 	id "java"
 }
diff --git a/samples/users-resource/samples-users-resource.gradle b/samples/users-resource/samples-users-resource.gradle
index 25adda2e..520ebb22 100644
--- a/samples/users-resource/samples-users-resource.gradle
+++ b/samples/users-resource/samples-users-resource.gradle
@@ -1,12 +1,15 @@
 plugins {
-	id "org.springframework.boot" version "3.2.2"
+	id "org.springframework.boot" version "4.0.0-SNAPSHOT"
 	id "io.spring.dependency-management" version "1.1.0"
 	id "java"
 }
 
 group = project.rootProject.group
 version = project.rootProject.version
-sourceCompatibility = "17"
+
+java {
+	sourceCompatibility = JavaVersion.VERSION_17
+}
 
 repositories {
 	mavenCentral()
diff --git a/samples/x509-certificate-generator/samples-x509-certificate-generator.gradle b/samples/x509-certificate-generator/samples-x509-certificate-generator.gradle
index 5fc2874e..ea730966 100644
--- a/samples/x509-certificate-generator/samples-x509-certificate-generator.gradle
+++ b/samples/x509-certificate-generator/samples-x509-certificate-generator.gradle
@@ -1,5 +1,5 @@
 plugins {
-	id "org.springframework.boot" version "3.2.2"
+	id "org.springframework.boot" version "4.0.0-SNAPSHOT"
 	id "io.spring.dependency-management" version "1.1.0"
 	id "java"
 }
@@ -13,6 +13,8 @@ java {
 
 repositories {
 	mavenCentral()
+	maven { url "https://repo.spring.io/milestone" }
+	maven { url "https://repo.spring.io/snapshot" }
 }
 
 dependencies {
diff --git a/settings.gradle b/settings.gradle
index d74ed2a5..02285b46 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -1,6 +1,9 @@
 pluginManagement {
 	repositories {
 		gradlePluginPortal()
+		mavenCentral()
+		maven { url "https://repo.spring.io/milestone" }
+		maven { url "https://repo.spring.io/snapshot" }
 	}
 }