diff --git a/build.sbt b/build.sbt
index 115604de..270635e4 100644
--- a/build.sbt
+++ b/build.sbt
@@ -66,7 +66,7 @@ val coreDeps = Seq(
 )).map(_ % Test)
 
 val scala213 = "2.13.18"
-ThisBuild / crossScalaVersions := Seq("2.12.20", scala213, "3.3.7")
+ThisBuild / crossScalaVersions := Seq("2.12.21", scala213, "3.3.7")
 
 ThisBuild / scalaVersion := scala213
 ThisBuild / tlBaseVersion := "0.10"