diff --git a/build.sc b/build.sc
index 83e6950..0abf415 100644
--- a/build.sc
+++ b/build.sc
@@ -23,7 +23,7 @@ trait PlatformConfig {
 object Mill011 extends PlatformConfig {
   override val millVersion = "0.11.0" // scala-steward:off
   override val millPlatform = "0.11"
-  override val testWith = Seq("0.11.7", millVersion)
+  override val testWith = Seq("0.12.4", "0.12.0", "0.11.13", millVersion)
 }
 object Mill010 extends PlatformConfig {
   override val millVersion = "0.10.0" // scala-steward:off