diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d7e51ca..d75cce9 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -28,7 +28,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        scala: [2.12.17, 2.13.8, 3.1.3]
+        scala: [2.12.17, 2.13.9, 3.1.3]
         java: [temurin@8]
         project: [rootJS, rootJVM, rootNative]
     runs-on: ${{ matrix.os }}
@@ -114,7 +114,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        scala: [2.13.8]
+        scala: [2.13.9]
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
@@ -181,32 +181,32 @@ jobs:
           tar xf targets.tar
           rm targets.tar
 
-      - name: Download target directories (2.13.8, rootJS)
+      - name: Download target directories (2.13.9, rootJS)
         uses: actions/download-artifact@v2
         with:
-          name: target-${{ matrix.os }}-${{ matrix.java }}-2.13.8-rootJS
+          name: target-${{ matrix.os }}-${{ matrix.java }}-2.13.9-rootJS
 
-      - name: Inflate target directories (2.13.8, rootJS)
+      - name: Inflate target directories (2.13.9, rootJS)
         run: |
           tar xf targets.tar
           rm targets.tar
 
-      - name: Download target directories (2.13.8, rootJVM)
+      - name: Download target directories (2.13.9, rootJVM)
         uses: actions/download-artifact@v2
         with:
-          name: target-${{ matrix.os }}-${{ matrix.java }}-2.13.8-rootJVM
+          name: target-${{ matrix.os }}-${{ matrix.java }}-2.13.9-rootJVM
 
-      - name: Inflate target directories (2.13.8, rootJVM)
+      - name: Inflate target directories (2.13.9, rootJVM)
         run: |
           tar xf targets.tar
           rm targets.tar
 
-      - name: Download target directories (2.13.8, rootNative)
+      - name: Download target directories (2.13.9, rootNative)
         uses: actions/download-artifact@v2
         with:
-          name: target-${{ matrix.os }}-${{ matrix.java }}-2.13.8-rootNative
+          name: target-${{ matrix.os }}-${{ matrix.java }}-2.13.9-rootNative
 
-      - name: Inflate target directories (2.13.8, rootNative)
+      - name: Inflate target directories (2.13.9, rootNative)
         run: |
           tar xf targets.tar
           rm targets.tar
@@ -260,7 +260,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        scala: [2.13.8]
+        scala: [2.13.9]
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
diff --git a/build.sbt b/build.sbt
index 657bbaf..f47c8c2 100644
--- a/build.sbt
+++ b/build.sbt
@@ -16,7 +16,7 @@ ThisBuild / tlSonatypeUseLegacyHost := false
 // publish website from this branch
 ThisBuild / tlSitePublishBranch := Some("main")
 
-val Scala213 = "2.13.8"
+val Scala213 = "2.13.9"
 ThisBuild / crossScalaVersions := Seq("2.12.17", Scala213, "3.1.3")
 ThisBuild / scalaVersion := Scala213 // the default Scala