diff --git a/opensearch-observability/build.gradle b/opensearch-observability/build.gradle
index c4ff339e7..bcd8e656e 100644
--- a/opensearch-observability/build.gradle
+++ b/opensearch-observability/build.gradle
@@ -13,7 +13,7 @@ buildscript {
         // 1.0.0 -> 1.0.0.0, and 1.0.0-SNAPSHOT -> 1.0.0.0-SNAPSHOT
         opensearch_build = opensearch_version.replaceAll(/(\.\d)([^\d]*)$/, '$1.0$2')
         common_utils_version = System.getProperty("common_utils.version", opensearch_build)
-        kotlin_version = System.getProperty("kotlin.version", "1.4.0")
+        kotlin_version = System.getProperty("kotlin.version", "1.6.0")
     }
 
     repositories {
@@ -28,7 +28,7 @@ buildscript {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:${kotlin_version}"
         classpath "org.jetbrains.kotlin:kotlin-allopen:${kotlin_version}"
         classpath "io.gitlab.arturbosch.detekt:detekt-gradle-plugin:1.12.0"
-        classpath "org.jacoco:org.jacoco.agent:0.8.5"
+        classpath "org.jacoco:org.jacoco.agent:0.8.7"
     }
 }
 
@@ -117,6 +117,7 @@ allprojects {
     plugins.withId('java') {
         sourceCompatibility = targetCompatibility = "1.8"
     }
+    jacoco.toolVersion = "0.8.7"
 }
 
 dependencies {
diff --git a/opensearch-observability/src/main/kotlin/org/opensearch/observability/settings/PluginSettings.kt b/opensearch-observability/src/main/kotlin/org/opensearch/observability/settings/PluginSettings.kt
index 0f5d31504..ae1eead9b 100644
--- a/opensearch-observability/src/main/kotlin/org/opensearch/observability/settings/PluginSettings.kt
+++ b/opensearch-observability/src/main/kotlin/org/opensearch/observability/settings/PluginSettings.kt
@@ -8,6 +8,7 @@ package org.opensearch.observability.settings
 import org.apache.logging.log4j.LogManager
 import org.opensearch.bootstrap.BootstrapInfo
 import org.opensearch.cluster.service.ClusterService
+import org.opensearch.common.io.PathUtils
 import org.opensearch.common.settings.Setting
 import org.opensearch.common.settings.Setting.Property.Dynamic
 import org.opensearch.common.settings.Setting.Property.NodeScope
@@ -15,7 +16,6 @@ import org.opensearch.common.settings.Settings
 import org.opensearch.observability.ObservabilityPlugin.Companion.LOG_PREFIX
 import org.opensearch.observability.ObservabilityPlugin.Companion.PLUGIN_NAME
 import java.io.IOException
-import java.nio.file.Paths
 
 /**
  * settings specific to observability Plugin.
@@ -246,7 +246,7 @@ internal object PluginSettings {
         var settings: Settings? = null
         val configDirName = BootstrapInfo.getSystemProperties()?.get("opensearch.path.conf")?.toString()
         if (configDirName != null) {
-            val defaultSettingYmlFile = Paths.get(configDirName, PLUGIN_NAME, "observability.yml")
+            val defaultSettingYmlFile = PathUtils.get(configDirName, PLUGIN_NAME, "observability.yml")
             try {
                 settings = Settings.builder().loadFromPath(defaultSettingYmlFile).build()
             } catch (exception: IOException) {
diff --git a/opensearch-observability/src/test/kotlin/org/opensearch/observability/PluginRestTestCase.kt b/opensearch-observability/src/test/kotlin/org/opensearch/observability/PluginRestTestCase.kt
index c80e1bddd..c19166a27 100644
--- a/opensearch-observability/src/test/kotlin/org/opensearch/observability/PluginRestTestCase.kt
+++ b/opensearch-observability/src/test/kotlin/org/opensearch/observability/PluginRestTestCase.kt
@@ -26,6 +26,7 @@ import org.opensearch.client.Response
 import org.opensearch.client.ResponseException
 import org.opensearch.client.RestClient
 import org.opensearch.client.RestClientBuilder
+import org.opensearch.common.io.PathUtils
 import org.opensearch.common.settings.Settings
 import org.opensearch.common.unit.TimeValue
 import org.opensearch.common.util.concurrent.ThreadContext
@@ -38,7 +39,6 @@ import java.io.IOException
 import java.io.InputStreamReader
 import java.nio.charset.StandardCharsets
 import java.nio.file.Files
-import java.nio.file.Paths
 import java.security.cert.X509Certificate
 import javax.management.MBeanServerInvocationHandler
 import javax.management.ObjectName
@@ -263,7 +263,7 @@ abstract class PluginRestTestCase : OpenSearchRestTestCase() {
                     false
                 )
                 proxy.getExecutionData(false)?.let {
-                    val path = Paths.get("$jacocoBuildPath/integTest.exec")
+                    val path = PathUtils.get("$jacocoBuildPath/integTest.exec")
                     Files.write(path, it)
                 }
             }
diff --git a/opensearch-observability/src/test/kotlin/org/opensearch/observability/bwc/TABackwardCompatibilityIT.kt b/opensearch-observability/src/test/kotlin/org/opensearch/observability/bwc/TABackwardCompatibilityIT.kt
index cc709de4a..6fe5fcf12 100644
--- a/opensearch-observability/src/test/kotlin/org/opensearch/observability/bwc/TABackwardCompatibilityIT.kt
+++ b/opensearch-observability/src/test/kotlin/org/opensearch/observability/bwc/TABackwardCompatibilityIT.kt
@@ -13,8 +13,6 @@ import org.opensearch.observability.PluginRestTestCase
 import org.opensearch.observability.constructNotebookRequest
 import org.opensearch.rest.RestRequest
 import org.opensearch.rest.RestStatus
-import java.util.List
-import java.util.Map
 
 class TABackwardCompatibilityIT : PluginRestTestCase() {
 
@@ -61,14 +59,14 @@ class TABackwardCompatibilityIT : PluginRestTestCase() {
     }
 
     @Throws(Exception::class)
-    @SuppressWarnings("unchecked")
+    @SuppressWarnings("UNCHECKED_CAST")
     fun `test backwards compatibility`() {
         val uri = getUri()
         val responseMap = getAsMap(uri)["nodes"] as Map<String, Map<String, Any>>
-        for (response in responseMap.values()) {
+        for (response in responseMap.values) {
             val plugins = response["plugins"] as List<Map<String, Any>>
             val pluginNames = plugins.map { plugin -> plugin["name"] }.toSet()
-            return when (CLUSTER_TYPE) {
+            when (CLUSTER_TYPE) {
                 ClusterType.OLD -> {
                     assertTrue(pluginNames.contains("opensearch-notebooks"))
                     createNotebook()