diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b6a7630..b4dcf0d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -29,20 +29,24 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-22.04]
-        scala: [2.12, 2.13, 3]
+        scala: [2.12.21, 3.9.0, 3.3.8]
         java: [temurin@17, temurin@8, temurin@11]
         exclude:
-          - scala: 2.12
+          - scala: 2.12.21
             java: temurin@8
-          - scala: 2.12
+          - scala: 2.12.21
             java: temurin@11
-          - scala: 3
+          - scala: 3.3.8
             java: temurin@8
-          - scala: 3
+          - scala: 3.3.8
             java: temurin@11
-          - scala: 3
+          - scala: 3.9.0
             java: temurin@8
-          - scala: 3
+          - scala: 3.9.0
+            java: temurin@11
+          - scala: 3.3.8
+            java: temurin@8
+          - scala: 3.3.8
             java: temurin@11
     runs-on: ${{ matrix.os }}
     timeout-minutes: 60
@@ -192,32 +196,32 @@ jobs:
         if: matrix.java == 'temurin@11' && steps.setup-java-temurin-11.outputs.cache-hit == 'false'
         run: sbt +update
 
-      - name: Download target directories (2.12)
+      - name: Download target directories (2.12.21)
         uses: actions/download-artifact@v6
         with:
-          name: target-${{ matrix.os }}-${{ matrix.java }}-2.12
+          name: target-${{ matrix.os }}-${{ matrix.java }}-2.12.21
 
-      - name: Inflate target directories (2.12)
+      - name: Inflate target directories (2.12.21)
         run: |
           tar xf targets.tar
           rm targets.tar
 
-      - name: Download target directories (2.13)
+      - name: Download target directories (3.9.0)
         uses: actions/download-artifact@v6
         with:
-          name: target-${{ matrix.os }}-${{ matrix.java }}-2.13
+          name: target-${{ matrix.os }}-${{ matrix.java }}-3.9.0
 
-      - name: Inflate target directories (2.13)
+      - name: Inflate target directories (3.9.0)
         run: |
           tar xf targets.tar
           rm targets.tar
 
-      - name: Download target directories (3)
+      - name: Download target directories (3.3.8)
         uses: actions/download-artifact@v6
         with:
-          name: target-${{ matrix.os }}-${{ matrix.java }}-3
+          name: target-${{ matrix.os }}-${{ matrix.java }}-3.3.8
 
-      - name: Inflate target directories (3)
+      - name: Inflate target directories (3.3.8)
         run: |
           tar xf targets.tar
           rm targets.tar
@@ -305,7 +309,7 @@ jobs:
       - name: Submit Dependencies
         uses: scalacenter/sbt-dependency-submission@v2
         with:
-          modules-ignore: root_2.12 root_2.13 root_3 docs_2.12 docs_2.13 docs_3 sbt-http4s-org-scalafix-internal_2.12 sbt-http4s-org-scalafix-internal_2.13 sbt-http4s-org-scalafix-internal_3
+          modules-ignore: root_2.12 root_3 root_3 docs_2.12 docs_3 docs_3 sbt-http4s-org-scalafix-internal_2.12 sbt-http4s-org-scalafix-internal_3 sbt-http4s-org-scalafix-internal_3
           configs-ignore: test scala-tool scala-doc-tool test-internal
 
   validate-steward:
diff --git a/build.sbt b/build.sbt
index 6512cb4..81c82c9 100644
--- a/build.sbt
+++ b/build.sbt
@@ -5,7 +5,7 @@ ThisBuild / developers := List(
 ThisBuild / startYear := Some(2014)
 
 val Scala212 = "2.12.21"
-val Scala213 = "2.13.18"
+val Scala213 = "3.9.0"
 ThisBuild / crossScalaVersions := Seq(Scala212, Scala213, "3.3.8")
 ThisBuild / scalaVersion := Scala213