diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 0b5f183..0e5ed9b 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -14,7 +14,7 @@ jobs:
   build:
     strategy:
       matrix:
-        scalaVersion: ["2.13.12", "3.3.4"]
+        scalaVersion: ["2.13.15", "3.3.4"]
     runs-on: ubuntu-22.04
 
     steps:
diff --git a/build.sbt b/build.sbt
index 686029e..44d4c88 100644
--- a/build.sbt
+++ b/build.sbt
@@ -27,8 +27,8 @@ inThisBuild(
 )
 
 lazy val commonSettings = Seq(
-  crossScalaVersions := Seq("2.13.12", "3.3.4"),
-  scalaVersion       := "2.13.12",
+  crossScalaVersions := Seq("2.13.15", "3.3.4"),
+  scalaVersion       := "2.13.15",
   libraryDependencies ++= (CrossVersion.partialVersion(scalaVersion.value) match {
     case Some((3, _)) => Seq.empty
     case _            =>
@@ -110,7 +110,7 @@ lazy val rx = project
   .settings(commonSettings)
   .settings(
     name               := "colibri-rx",
-    crossScalaVersions := Seq("2.13.12"), // no scala3, because scala.rx uses scala2 macros
+    crossScalaVersions := Seq("2.13.15"), // no scala3, because scala.rx uses scala2 macros
     libraryDependencies ++= Seq(
       "com.lihaoyi" %% "scalarx" % "0.4.3",
     ),