diff --git a/build.gradle.kts b/build.gradle.kts
index d5bb972..9eaecc7 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -178,9 +178,9 @@ allprojects {
     tasks {
         withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile::class) {
             with(kotlinOptions) {
-                freeCompilerArgs = listOf("-Xjvm-default=all", "-Xlambdas=indy")
+                freeCompilerArgs = listOf("-Xjvm-default=all", "-Xlambdas=indy", "-progressive")
                 jvmTarget = if (javaVer.toInt() < 10) "1.$javaVer" else javaVer
-                languageVersion = "1.5"
+                languageVersion = (kotlinBaseVer.toDouble() + 0.1).toString()
                 apiVersion = kotlinBaseVer
             }
         }