diff --git a/build.mill b/build.mill
index be24f6b..dbd382f 100644
--- a/build.mill
+++ b/build.mill
@@ -24,7 +24,7 @@ trait MillGitCross
     with GitVersionedPublishModule
     with SonatypeCentralPublishModule:
   val millVersion            = crossValue
-  override def scalaVersion  = "3.7.4"
+  override def scalaVersion  = "3.9.0"
   override def scalacOptions = super.scalacOptions() ++ ScalacOptions.tokensForVersion(
     ScalaVersion.unsafeFromString(scalaVersion()),
     ScalacOptions.default + source3 ++ fatalWarningOptions