diff --git a/.idea/kotlinc.xml b/.idea/kotlinc.xml
index f12916d7..1b15ab44 100644
--- a/.idea/kotlinc.xml
+++ b/.idea/kotlinc.xml
@@ -4,10 +4,11 @@
     <option name="jvmTarget" value="17" />
   </component>
   <component name="KotlinCommonCompilerArguments">
-    <option name="apiVersion" value="2.2" />
-    <option name="languageVersion" value="2.2" />
+    <option name="apiVersion" value="2.3.20" />
+    <option name="languageVersion" value="2.3.20" />
   </component>
   <component name="KotlinJpsPluginSettings">
-    <option name="version" value="2.2.21" />
+    <option name="externalSystemId" value="Gradle" />
+    <option name="version" value="2.3.20" />
   </component>
 </project>
diff --git a/buildSrc/build.gradle.kts b/buildSrc/build.gradle.kts
index 691d6b70..227e6d26 100644
--- a/buildSrc/build.gradle.kts
+++ b/buildSrc/build.gradle.kts
@@ -75,7 +75,7 @@ val grGitVersion = "4.1.1"
  * This version may change from the [version of Kotlin][io.spine.dependency.lib.Kotlin.version]
  * used by the project.
  */
-val kotlinEmbeddedVersion = "2.3.10"
+val kotlinEmbeddedVersion = "2.3.20"
 
 /**
  * The version of Guava used in `buildSrc`.
diff --git a/buildSrc/src/main/kotlin/io/spine/dependency/lib/Kotlin.kt b/buildSrc/src/main/kotlin/io/spine/dependency/lib/Kotlin.kt
index 11144301..ff4202fb 100644
--- a/buildSrc/src/main/kotlin/io/spine/dependency/lib/Kotlin.kt
+++ b/buildSrc/src/main/kotlin/io/spine/dependency/lib/Kotlin.kt
@@ -39,7 +39,7 @@ object Kotlin : DependencyWithBom() {
      * depend on Gradle and the version of embedded Kotlin.
      */
     @Suppress("MemberVisibilityCanBePrivate") // used directly from the outside.
-    const val runtimeVersion = "2.3.10"
+    const val runtimeVersion = "2.3.20"
 
     override val version = runtimeVersion
     override val group = "org.jetbrains.kotlin"
@@ -49,7 +49,7 @@ object Kotlin : DependencyWithBom() {
      * This is the version of
      * [Kotlin embedded into Gradle](https://docs.gradle.org/current/userguide/compatibility.html#kotlin).
      */
-    const val embeddedVersion = "2.2.21"
+    const val embeddedVersion = "2.3.20"
 
     /**
      * The version of the JetBrains annotations library, which is a transitive
diff --git a/buildSrc/src/main/kotlin/io/spine/dependency/lib/Protobuf.kt b/buildSrc/src/main/kotlin/io/spine/dependency/lib/Protobuf.kt
index 0a432d41..0200fe47 100644
--- a/buildSrc/src/main/kotlin/io/spine/dependency/lib/Protobuf.kt
+++ b/buildSrc/src/main/kotlin/io/spine/dependency/lib/Protobuf.kt
@@ -26,6 +26,9 @@
 
 package io.spine.dependency.lib
 
+import io.spine.dependency.lib.Protobuf.GradlePlugin.id
+
+
 // https://github.com/protocolbuffers/protobuf
 @Suppress(
     "MemberVisibilityCanBePrivate" /* used directly from the outside */,
@@ -33,7 +36,7 @@ package io.spine.dependency.lib
 )
 object Protobuf {
     const val group = "com.google.protobuf"
-    const val version = "4.34.0"
+    const val version = "4.34.1"
 
     /**
      * The Java library with Protobuf data types.
diff --git a/buildSrc/src/main/kotlin/io/spine/dependency/local/Base.kt b/buildSrc/src/main/kotlin/io/spine/dependency/local/Base.kt
index 7e4b1c3b..b999a75d 100644
--- a/buildSrc/src/main/kotlin/io/spine/dependency/local/Base.kt
+++ b/buildSrc/src/main/kotlin/io/spine/dependency/local/Base.kt
@@ -33,8 +33,8 @@ package io.spine.dependency.local
  */
 @Suppress("ConstPropertyName", "unused")
 object Base {
-    const val version = "2.0.0-SNAPSHOT.385"
-    const val versionForBuildScript = "2.0.0-SNAPSHOT.385"
+    const val version = "2.0.0-SNAPSHOT.386"
+    const val versionForBuildScript = "2.0.0-SNAPSHOT.386"
     const val group = Spine.group
     private const val prefix = "spine"
     const val libModule = "$prefix-base"
diff --git a/buildSrc/src/main/kotlin/io/spine/dependency/local/Compiler.kt b/buildSrc/src/main/kotlin/io/spine/dependency/local/Compiler.kt
index b3a708b3..3be79eb7 100644
--- a/buildSrc/src/main/kotlin/io/spine/dependency/local/Compiler.kt
+++ b/buildSrc/src/main/kotlin/io/spine/dependency/local/Compiler.kt
@@ -77,7 +77,7 @@ object Compiler : Dependency() {
      * The version of the Compiler dependencies.
      */
     override val version: String
-    private const val fallbackVersion = "2.0.0-SNAPSHOT.040"
+    private const val fallbackVersion = "2.0.0-SNAPSHOT.041"
 
     /**
      * The distinct version of the Compiler used by other build tools.
@@ -86,7 +86,7 @@ object Compiler : Dependency() {
      * transitive dependencies, this is the version used to build the project itself.
      */
     val dogfoodingVersion: String
-    private const val fallbackDfVersion = "2.0.0-SNAPSHOT.039"
+    private const val fallbackDfVersion = "2.0.0-SNAPSHOT.041"
 
     /**
      * The artifact for the Compiler Gradle plugin.
diff --git a/buildSrc/src/main/kotlin/io/spine/dependency/local/ToolBase.kt b/buildSrc/src/main/kotlin/io/spine/dependency/local/ToolBase.kt
index 5e443139..872127af 100644
--- a/buildSrc/src/main/kotlin/io/spine/dependency/local/ToolBase.kt
+++ b/buildSrc/src/main/kotlin/io/spine/dependency/local/ToolBase.kt
@@ -34,8 +34,8 @@ package io.spine.dependency.local
 @Suppress("ConstPropertyName", "unused")
 object ToolBase {
     const val group = Spine.toolsGroup
-    const val version = "2.0.0-SNAPSHOT.373"
-    const val dogfoodingVersion = "2.0.0-SNAPSHOT.373"
+    const val version = "2.0.0-SNAPSHOT.375"
+    const val dogfoodingVersion = "2.0.0-SNAPSHOT.375"
 
     const val lib = "$group:tool-base:$version"
     const val classicCodegen = "$group:classic-codegen:$version"
diff --git a/buildSrc/src/main/kotlin/io/spine/dependency/local/Validation.kt b/buildSrc/src/main/kotlin/io/spine/dependency/local/Validation.kt
index 327c6114..e10eea54 100644
--- a/buildSrc/src/main/kotlin/io/spine/dependency/local/Validation.kt
+++ b/buildSrc/src/main/kotlin/io/spine/dependency/local/Validation.kt
@@ -36,7 +36,7 @@ object Validation {
     /**
      * The version of the Validation library artifacts.
      */
-    const val version = "2.0.0-SNAPSHOT.405"
+    const val version = "2.0.0-SNAPSHOT.406"
 
     /**
      * The last version of Validation compatible with ProtoData.
diff --git a/buildSrc/src/main/kotlin/io/spine/gradle/kotlin/KotlinConfig.kt b/buildSrc/src/main/kotlin/io/spine/gradle/kotlin/KotlinConfig.kt
index 5e3c8922..92b7a387 100644
--- a/buildSrc/src/main/kotlin/io/spine/gradle/kotlin/KotlinConfig.kt
+++ b/buildSrc/src/main/kotlin/io/spine/gradle/kotlin/KotlinConfig.kt
@@ -61,7 +61,6 @@ fun KotlinCommonCompilerOptions.setFreeCompilerArgs() {
     freeCompilerArgs.addAll(
         listOf(
             "-Xskip-prerelease-check",
-            "-Xinline-classes",
             "-Xexpect-actual-classes",
             "-Xcontext-parameters",
             "-opt-in=" +
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index dbc3ce4a..c61a118f 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.4.0-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.4.1-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME
diff --git a/gradlew b/gradlew
index 0262dcbd..739907df 100755
--- a/gradlew
+++ b/gradlew
@@ -57,7 +57,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/b631911858264c0b6e4d6603d677ff5218766cee/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/2d6327017519d23b96af35865dc997fcb544fb40/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.