diff --git a/build.gradle.kts b/build.gradle.kts
index 27e673222..1953ff732 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -180,8 +180,8 @@ subprojects {
             sourceSets {
                 all {
                     languageSettings.apply {
-                        languageVersion = "1.5"
-                        apiVersion = "1.5"
+                        languageVersion = "1.9"
+                        apiVersion = "1.9"
                     }
                 }
                 val commonMain by getting {
diff --git a/cli/src/commonMain/kotlin/org/islandoftex/arara/cli/utils/DisplayUtils.kt b/cli/src/commonMain/kotlin/org/islandoftex/arara/cli/utils/DisplayUtils.kt
index dff09221f..00c758003 100644
--- a/cli/src/commonMain/kotlin/org/islandoftex/arara/cli/utils/DisplayUtils.kt
+++ b/cli/src/commonMain/kotlin/org/islandoftex/arara/cli/utils/DisplayUtils.kt
@@ -13,7 +13,7 @@ import org.islandoftex.arara.core.session.Session
 import org.islandoftex.arara.core.utils.formatString
 import kotlin.math.ln
 import kotlin.math.pow
-import kotlin.time.Duration
+import kotlin.time.Duration.Companion.seconds
 
 /**
  * Implements display utilitary methods.
@@ -323,14 +323,14 @@ object DisplayUtils {
         if (displayLine || displayException)
             println()
 
-        val secondDuration = Duration.seconds(seconds)
+        val secondDuration = seconds.seconds
         val text = LanguageController.messages.INFO_DISPLAY_EXECUTION_TIME
             .formatString(
                 "%s%s%s".formatString(
                     secondDuration.inWholeSeconds.toString(),
                     Session.userInterfaceOptions.locale
                         .decimalSeparator.toString(),
-                    (secondDuration - Duration.seconds(secondDuration.inWholeSeconds))
+                    (secondDuration - secondDuration.inWholeSeconds.seconds)
                         .inWholeMilliseconds.toString()
                 )
             )
diff --git a/cli/src/jvmMain/kotlin/org/islandoftex/arara/cli/CLI.kt b/cli/src/jvmMain/kotlin/org/islandoftex/arara/cli/CLI.kt
index 8dd565cce..aeb796167 100644
--- a/cli/src/jvmMain/kotlin/org/islandoftex/arara/cli/CLI.kt
+++ b/cli/src/jvmMain/kotlin/org/islandoftex/arara/cli/CLI.kt
@@ -44,7 +44,7 @@ import org.islandoftex.arara.core.session.Session
 import org.islandoftex.arara.lua.LuaInterpreter
 import org.islandoftex.arara.mvel.utils.MvelState
 import java.time.LocalDate
-import kotlin.time.Duration
+import kotlin.time.Duration.Companion.milliseconds
 import kotlin.time.DurationUnit
 import kotlin.time.TimeSource
 
@@ -199,7 +199,7 @@ class CLI : CliktCommand(
             .copy(
                 maxLoops = maxLoops
                     ?: LinearExecutor.executionOptions.maxLoops,
-                timeoutValue = timeout?.let { Duration.milliseconds(it) }
+                timeoutValue = timeout?.let { it.milliseconds }
                     ?: LinearExecutor.executionOptions.timeoutValue,
                 verbose = if (verbose)
                     true