diff --git a/build.gradle.kts b/build.gradle.kts
index 55749d4..058771a 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -63,6 +63,6 @@ release {
 // when version changes :
 // -> execute ./gradlew wrapper, then delete .gradle directory, then execute ./gradlew wrapper again
 tasks.wrapper {
-    gradleVersion = "6.7"
+    gradleVersion = "7.0"
     distributionType = Wrapper.DistributionType.ALL
 }
diff --git a/gradle.properties b/gradle.properties
index 4c3fea2..2590997 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,20 +1,20 @@
 group=org.ufoss.kolog
-version=0.4
+version=0.4-beta1
 
 # plugins
-kotlinVersion=1.4.10
-dokkaPluginVersion=1.4.10.2
+kotlinVersion=1.4.32
+dokkaPluginVersion=1.4.30
 releasePluginVersion=2.8.1
-androidLibraryPluginVersion=4.0.0
+androidLibraryPluginVersion=4.1.0
 
 # main
 slf4jVersion=1.7.30
 
 # tests
 # https://mvnrepository.com/artifact/org.junit.jupiter/junit-jupiter-api
-junitVersion=5.7.0
+junitVersion=5.7.1
 logbackVersion=1.2.3
-kotlinxCoroutinesVersion=1.4.0
+kotlinxCoroutinesVersion=1.4.3
 
 # multiplatform
 kotlin.mpp.enableGranularSourceSetsMetadata=true
@@ -27,8 +27,5 @@ android.useAndroidX=true
 org.gradle.vfs.watch=true
 kotlin.code.style=official
 org.gradle.warning.mode=all
-# Workaround for Bintray treating .sha512 files as artifacts
-# https://github.com/gradle/gradle/issues/11412
-systemProp.org.gradle.internal.publish.checksums.insecure=true
 # to solve java.lang.OutOfMemoryError: Metaspace
 org.gradle.jvmargs=-XX:MaxMetaspaceSize=512m
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 14e30f7..3c4101c 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.0-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
diff --git a/kolog/src/androidMain/kotlin/org/ufoss/kolog/Logger.kt b/kolog/src/androidMain/kotlin/org/ufoss/kolog/Logger.kt
index 2887d66..86663d4 100644
--- a/kolog/src/androidMain/kotlin/org/ufoss/kolog/Logger.kt
+++ b/kolog/src/androidMain/kotlin/org/ufoss/kolog/Logger.kt
@@ -11,7 +11,7 @@ import android.util.Log
  */
 @Suppress("NON_PUBLIC_PRIMARY_CONSTRUCTOR_OF_INLINE_CLASS")
 public actual inline class Logger @PublishedApi internal constructor(
-        private val parameter: Parameter
+        @PublishedApi internal val parameter: Parameter
 ) : LoggerProperties {
     /**
      * Companion object for [Logger] class that contains its constructor functions
diff --git a/kolog/src/commonMain/kotlin/org/ufoss/kolog/Logger.kt b/kolog/src/commonMain/kotlin/org/ufoss/kolog/Logger.kt
index c902b3b..b385588 100644
--- a/kolog/src/commonMain/kotlin/org/ufoss/kolog/Logger.kt
+++ b/kolog/src/commonMain/kotlin/org/ufoss/kolog/Logger.kt
@@ -6,7 +6,7 @@ package org.ufoss.kolog
 
 @Suppress("NON_PUBLIC_PRIMARY_CONSTRUCTOR_OF_INLINE_CLASS")
 public expect inline class Logger internal constructor(
-        parameter: Parameter
+        internal val parameter: Parameter
 ): LoggerProperties {
     /**
      * Companion object for [Logger] class that contains its constructor functions
diff --git a/kolog/src/iosMain/kotlin/org/ufoss/kolog/Logger.kt b/kolog/src/iosMain/kotlin/org/ufoss/kolog/Logger.kt
index 54a38c8..e08bfe3 100644
--- a/kolog/src/iosMain/kotlin/org/ufoss/kolog/Logger.kt
+++ b/kolog/src/iosMain/kotlin/org/ufoss/kolog/Logger.kt
@@ -11,7 +11,7 @@ import platform.Foundation.NSLog
  */
 @Suppress("NON_PUBLIC_PRIMARY_CONSTRUCTOR_OF_INLINE_CLASS")
 public actual inline class Logger @PublishedApi internal constructor(
-        private val parameter: Parameter
+        @PublishedApi internal val parameter: Parameter
 ) : LoggerProperties {
     /**
      * Companion object for [Logger] class that contains its constructor functions