diff --git a/.circleci/config.yml b/.circleci/config.yml
deleted file mode 100644
index db2f8e3..0000000
--- a/.circleci/config.yml
+++ /dev/null
@@ -1,13 +0,0 @@
-version: 2.1
-
-orbs:
-  gradle: circleci/gradle@2.2.0
-  advanced-checkout: vsco/advanced-checkout@1.0.0
-
-workflows:
-  checkout-build-test:
-    jobs:
-      - advanced-checkout/shallow-checkout:
-          fetch_lfs: true
-      - gradle/test:
-          test_command: build
diff --git a/.github/workflows/gradle.yml b/.github/workflows/gradle.yml
index 72053f9..b5034fe 100644
--- a/.github/workflows/gradle.yml
+++ b/.github/workflows/gradle.yml
@@ -23,19 +23,17 @@ jobs:
 
     strategy:
       matrix:
-        java: [ '11', '17' ]
+        java: [ '11', '17', '21' ]
 
     name: Build under JDK ${{ matrix.Java }}
 
     steps:
     - name: Checkout github repo (+ download lfs dependencies)
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         lfs: true
-    - name: Checkout LFS objects
-      run: git lfs checkout
     - name: Set up JDK
-      uses: actions/setup-java@v3
+      uses: actions/setup-java@v4
       with:
         java-version: ${{ matrix.java }}
         distribution: 'zulu'
@@ -48,8 +46,8 @@ jobs:
         gradle-version: wrapper
         arguments: check build --stacktrace
     - name: Publish Test Report
-      uses: mikepenz/action-junit-report@v3
-      if: always()
+      uses: mikepenz/action-junit-report@v4
+      if: success() || failure()
       with:
-        report_paths: '**/build/test-results/test/TEST-*.xml'
+        report_paths: '**/TEST-*.xml'
 
diff --git a/.java-version b/.java-version
index b4de394..2dbc24b 100644
--- a/.java-version
+++ b/.java-version
@@ -1 +1 @@
-11
+11.0
diff --git a/build.gradle.kts b/build.gradle.kts
index 26ba46c..e1b046a 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -46,8 +46,13 @@ dependencies {
 }
 
 group = "com.github.kpavlov.jreactive8583"
-version = if (findProperty("version") != "unspecified") findProperty("version")
-else "0.0.1-SNAPSHOT"
+version = (
+    if (findProperty("version") != "unspecified") {
+        findProperty("version")!!
+    } else {
+        "0.0.1-SNAPSHOT"
+    }
+    )
 description = "ISO8583 Connector for Netty"
 java.sourceCompatibility = JavaVersion.VERSION_11
 java.targetCompatibility = JavaVersion.VERSION_11
@@ -68,7 +73,9 @@ tasks.test {
     useJUnitPlatform()
     testLogging {
         events = setOf(
-            TestLogEvent.PASSED, TestLogEvent.SKIPPED, TestLogEvent.FAILED
+            TestLogEvent.PASSED,
+            TestLogEvent.SKIPPED,
+            TestLogEvent.FAILED
         )
     }
 }