diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 474383bb..fd899bbc 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,29 +11,32 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, windows-latest]
         include:
-          - java: 8
-            scala: 2.12.8
-          - java: 11
-            scala: 2.12.8
+          - os: ubuntu-latest
+            java: 8
+            distribution: temurin
+          - os: ubuntu-latest
+            java: 11
+            distribution: temurin
+          - os: ubuntu-latest
+            java: 21
+            distribution: temurin
+          - os: windows-latest
+            java: 11
+            distribution: temurin
     env:
       # define Java options for both official sbt and sbt-extras
       JAVA_OPTS: -Xms2048M -Xmx2048M -Xss6M -XX:ReservedCodeCacheSize=256M -Dfile.encoding=UTF-8
       JVM_OPTS:  -Xms2048M -Xmx2048M -Xss6M -XX:ReservedCodeCacheSize=256M -Dfile.encoding=UTF-8
     steps:
-    - uses: actions/checkout@v2
-    - uses: olafurpg/setup-scala@v10
+    - uses: actions/checkout@v4
+    - name: Setup JDK
+      uses: actions/setup-java@v3
       with:
-        java-version: "adopt@1.${{ matrix.java }}"
-    - uses: coursier/cache-action@v5
+        distribution: "${{ matrix.distribution }}"
+        java-version: "${{ matrix.java }}"
+        cache: sbt
     - name: Build and test
       shell: bash
       run: |
-        sbt -v +publishLocal $(if [[ "${{matrix.scala}}" != "" ]] ; then echo "++${{matrix.scala}}!" ; fi) test scripted
-        rm -rf "$HOME/.ivy2/local" || true
-        rm -rf "$HOME/.ivy2/cache/com.eed3si9n" || true
-        find $HOME/Library/Caches/Coursier/v1        -name "ivydata-*.properties" -delete || true
-        find $HOME/.ivy2/cache                       -name "ivydata-*.properties" -delete || true
-        find $HOME/.cache/coursier/v1                -name "ivydata-*.properties" -delete || true
-        find $HOME/.sbt                              -name "*.lock"               -delete || true
+        sbt -v clean scripted
diff --git a/.java-version b/.java-version
deleted file mode 100644
index 62593409..00000000
--- a/.java-version
+++ /dev/null
@@ -1 +0,0 @@
-1.8
diff --git a/build.sbt b/build.sbt
index 6d67648a..6b8c3041 100644
--- a/build.sbt
+++ b/build.sbt
@@ -6,12 +6,12 @@ ThisBuild / version := {
 
 ThisBuild / organization := "com.eed3si9n"
 
-def scala212 = "2.12.8"
+def scala212 = "2.12.18"
 ThisBuild / crossScalaVersions := Seq(scala212)
 ThisBuild / scalaVersion := scala212
 
 lazy val root = (project in file("."))
-  .enablePlugins(SbtPlugin, ContrabandPlugin)
+  .enablePlugins(SbtPlugin, ContrabandPlugin, SbtPlugin)
   .settings(pomConsistency2021DraftSettings)
   .settings(nocomma {
     name := "sbt-assembly"
@@ -25,6 +25,11 @@ lazy val root = (project in file("."))
       }
     }
     Compile / generateContrabands / sourceManaged := baseDirectory.value / "src" / "main" / "scala"
+    scriptedLaunchOpts := { scriptedLaunchOpts.value ++
+      Seq("-Xmx1024M", "-Dplugin.version=" + version.value)
+    }
+    scriptedBufferLog := false
+    scriptedSbt := "1.9.7"
   })
 
 ThisBuild / scmInfo := Some(
diff --git a/project/build.properties b/project/build.properties
index 27430827..e8a1e246 100644
--- a/project/build.properties
+++ b/project/build.properties
@@ -1 +1 @@
-sbt.version=1.9.6
+sbt.version=1.9.7
diff --git a/scripted.sbt b/scripted.sbt
deleted file mode 100644
index 3f03da39..00000000
--- a/scripted.sbt
+++ /dev/null
@@ -1,7 +0,0 @@
-enablePlugins(SbtPlugin)
-
-scriptedLaunchOpts := { scriptedLaunchOpts.value ++
-  Seq("-Xmx1024M", "-XX:MaxPermSize=256M", "-Dplugin.version=" + version.value)
-}
-
-scriptedBufferLog := false
diff --git a/src/sbt-test/sbt-assembly/timestamp/project/build.properties b/src/sbt-test/sbt-assembly/timestamp/project/build.properties
deleted file mode 100644
index 10fd9eee..00000000
--- a/src/sbt-test/sbt-assembly/timestamp/project/build.properties
+++ /dev/null
@@ -1 +0,0 @@
-sbt.version=1.5.5