diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c73b9c4..0489f01 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -28,10 +28,12 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        scala: [2.13, 3]
+        scala: [2.13, 2.12, 3]
         java: [temurin@8, temurin@17]
         project: [rootJS, rootJVM, rootNative]
         exclude:
+          - scala: 2.12
+            java: temurin@17
           - scala: 3
             java: temurin@17
           - project: rootJS
@@ -196,6 +198,36 @@ jobs:
           tar xf targets.tar
           rm targets.tar
 
+      - name: Download target directories (2.12, rootJS)
+        uses: actions/download-artifact@v4
+        with:
+          name: target-${{ matrix.os }}-${{ matrix.java }}-2.12-rootJS
+
+      - name: Inflate target directories (2.12, rootJS)
+        run: |
+          tar xf targets.tar
+          rm targets.tar
+
+      - name: Download target directories (2.12, rootJVM)
+        uses: actions/download-artifact@v4
+        with:
+          name: target-${{ matrix.os }}-${{ matrix.java }}-2.12-rootJVM
+
+      - name: Inflate target directories (2.12, rootJVM)
+        run: |
+          tar xf targets.tar
+          rm targets.tar
+
+      - name: Download target directories (2.12, rootNative)
+        uses: actions/download-artifact@v4
+        with:
+          name: target-${{ matrix.os }}-${{ matrix.java }}-2.12-rootNative
+
+      - name: Inflate target directories (2.12, rootNative)
+        run: |
+          tar xf targets.tar
+          rm targets.tar
+
       - name: Download target directories (3, rootJS)
         uses: actions/download-artifact@v4
         with:
@@ -297,7 +329,7 @@ jobs:
       - name: Submit Dependencies
         uses: scalacenter/sbt-dependency-submission@v2
         with:
-          modules-ignore: rootjs_2.13 rootjs_3 rootjvm_2.13 rootjvm_3 rootnative_2.13 rootnative_3
+          modules-ignore: rootjs_2.13 rootjs_2.12 rootjs_3 rootjvm_2.13 rootjvm_2.12 rootjvm_3 rootnative_2.13 rootnative_2.12 rootnative_3
           configs-ignore: test scala-tool scala-doc-tool test-internal
 
   coverage:
@@ -305,7 +337,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        scala: [2.13, 3]
+        scala: [2.13, 2.12, 3]
         java: [temurin@11]
     runs-on: ${{ matrix.os }}
     steps:
diff --git a/build.sbt b/build.sbt
index 620d46e..0506cbf 100644
--- a/build.sbt
+++ b/build.sbt
@@ -2,6 +2,7 @@ import sbtcrossproject.{ CrossType, crossProject }
 
 val Scala213V = "2.13.14"
 val Scala3V = "3.3.3"
+val Scala212V = "2.12.19"
 
 val circeVersion = "0.14.9"
 
@@ -14,7 +15,7 @@ ThisBuild / tlBaseVersion := "0.15"
 ThisBuild / tlCiReleaseTags := true
 
 ThisBuild / organization := "io.circe"
-ThisBuild / crossScalaVersions := List(Scala213V, Scala3V)
+ThisBuild / crossScalaVersions := List(Scala213V, Scala212V, Scala3V)
 ThisBuild / scalaVersion := Scala213V
 
 ThisBuild / githubWorkflowJavaVersions := Seq("8", "17").map(JavaSpec.temurin)