diff --git a/project/Jdk9.scala b/project/Jdk9.scala
index ac4d1871bb..12275d13bc 100644
--- a/project/Jdk9.scala
+++ b/project/Jdk9.scala
@@ -17,9 +17,8 @@ import sbt._
 object Jdk9 extends AutoPlugin {
   import JdkOptions.JavaVersion._
 
-  // The version 17 is special for any Java versions >= 17
-  // and the version 21 is special for any Java versions >= 21
-  private val supportedJavaLTSVersions = List("17", "21")
+  // The version 21 is special for any Java versions >= 21
+  private val supportedJavaLTSVersions = List("21")
 
   lazy val CompileJdk9 = config("CompileJdk9").extend(Compile)
 
diff --git a/project/JdkOptions.scala b/project/JdkOptions.scala
index 10bc38c945..d8f3a94b02 100644
--- a/project/JdkOptions.scala
+++ b/project/JdkOptions.scala
@@ -19,12 +19,12 @@ import sbt.librarymanagement.VersionNumber
 
 object JdkOptions extends AutoPlugin {
 
-  lazy val specificationVersion: String = sys.props("java.specification.version")
-
   object JavaVersion {
     val majorVersion: Int = java.lang.Runtime.version().feature()
   }
 
+  val targetJavaVersion = "17"
+
   lazy val versionSpecificJavaOptions =
     // for virtual threads
     "--add-opens=java.base/jdk.internal.misc=ALL-UNNAMED" ::
@@ -35,7 +35,9 @@ object JdkOptions extends AutoPlugin {
     "--add-opens=java.base/java.nio=ALL-UNNAMED" :: Nil
 
   def targetJdkScalacOptions(scalaVersion: String): Seq[String] =
-    Seq(if (scalaVersion.startsWith("3.")) "-Xtarget:17" else "release:17")
+    Seq("-release", JdkOptions.targetJavaVersion) ++ {
+      if (scalaVersion.startsWith("3.")) Seq(s"-Xtarget:${targetJavaVersion}") else Seq.empty
+    }
 
-  val targetJdkJavacOptions = Seq("-source", "17", "-target", "17")
+  val targetJdkJavacOptions = Seq("--release", targetJavaVersion)
 }
diff --git a/stream-tests-tck/src/test/scala-jdk9-only/org/apache/pekko/stream/tck/IterablePublisherViaJavaFlowPublisherTest.scala b/stream-tests-tck/src/test/scala/org/apache/pekko/stream/tck/IterablePublisherViaJavaFlowPublisherTest.scala
similarity index 94%
rename from stream-tests-tck/src/test/scala-jdk9-only/org/apache/pekko/stream/tck/IterablePublisherViaJavaFlowPublisherTest.scala
rename to stream-tests-tck/src/test/scala/org/apache/pekko/stream/tck/IterablePublisherViaJavaFlowPublisherTest.scala
index 079f7c1d3d..44706c2456 100644
--- a/stream-tests-tck/src/test/scala-jdk9-only/org/apache/pekko/stream/tck/IterablePublisherViaJavaFlowPublisherTest.scala
+++ b/stream-tests-tck/src/test/scala/org/apache/pekko/stream/tck/IterablePublisherViaJavaFlowPublisherTest.scala
@@ -17,7 +17,7 @@ import java.util.concurrent.{ Flow => JavaFlow }
 
 import org.apache.pekko
 import pekko.NotUsed
-import pekko.stream.scaladsl.{ Flow, JavaFlowSupport, Sink, Source }
+import pekko.stream.scaladsl.{ JavaFlowSupport, Sink, Source }
 import org.reactivestreams._
 
 class IterablePublisherViaJavaFlowPublisherTest extends PekkoPublisherVerification[Int] {