diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 587693d9..4dce1733 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,9 +8,7 @@ on:
 
 jobs:
   build:
-    # With ubuntu-latest (20.04), some tests using self signed SSL cert suddenly failed at version 20210614.1.
-    # The issue may be fixed later, but I'll use ubuntu-18.04 for a while as a workaround.
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     strategy:
       matrix:
         java_version: [8, 11]
@@ -39,7 +37,7 @@ jobs:
       run: ./gradlew -p fluency-aws-s3 check jacocoTestReport coveralls --stacktrace --info
 
   build_ext:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     strategy:
       matrix:
         java_version: [16, 17]
@@ -66,7 +64,7 @@ jobs:
   # can use Fluecy jars built with JDK 8 without any problem.
   # We're using --release option to build source code with JDK 8. So JDK 17 should work here.
   prepare_for_integration_test:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3
     - name: Set up JDK 17
@@ -79,7 +77,7 @@ jobs:
         path: |
           ~/.gradle/caches
           ~/.gradle/wrapper
-        key: ${{ runner.os }}-11-gradle-${{ hashFiles('**/*.gradle*') }}
+        key: ${{ runner.os }}-17-gradle-${{ hashFiles('**/*.gradle*') }}
     - name: Install local maven package
       run: |
         ./gradlew -p fluency-core publishToMavenLocal --stacktrace --info
@@ -91,7 +89,7 @@ jobs:
         path: ~/.m2
 
   integration_test:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     needs: prepare_for_integration_test
     strategy:
       matrix:
@@ -124,7 +122,7 @@ jobs:
         cd tests/mutual-tls && ./run.sh
 
   integration_ext_test:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     strategy:
       matrix:
         java_version: [16, 17]
diff --git a/build.gradle.kts b/build.gradle.kts
index 3b72dda3..5a3b505b 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -13,7 +13,7 @@ plugins {
   signing
   `maven-publish`
   id("com.github.kt3k.coveralls") version "2.12.0"
-  id("com.github.johnrengelman.shadow") version "7.1.2"
+  id("com.github.johnrengelman.shadow") version "8.1.1"
 }
 
 subprojects {
@@ -33,22 +33,22 @@ subprojects {
   }
 
   dependencies {
-    implementation("org.slf4j:slf4j-api:2.0.6")
-    implementation("org.msgpack:jackson-dataformat-msgpack:0.9.3")
+    implementation("org.slf4j:slf4j-api:2.0.9")
+    implementation("org.msgpack:jackson-dataformat-msgpack:0.9.6")
     implementation("org.komamitsu:phi-accural-failure-detector:0.0.5")
     implementation("net.jodah:failsafe:2.4.4")
 
-    testImplementation("org.junit.jupiter:junit-jupiter-api:5.9.1")
-    testImplementation("org.junit.jupiter:junit-jupiter-engine:5.9.1")
-    testImplementation("org.junit.jupiter:junit-jupiter-params:5.9.1")
-    testImplementation("ch.qos.logback:logback-classic:1.2.11")
+    testImplementation("org.junit.jupiter:junit-jupiter-api:5.10.1")
+    testImplementation("org.junit.jupiter:junit-jupiter-engine:5.10.1")
+    testImplementation("org.junit.jupiter:junit-jupiter-params:5.10.1")
+    testImplementation("ch.qos.logback:logback-classic:1.2.12")
     testImplementation("org.hamcrest:hamcrest-all:1.3")
-    testImplementation("org.mockito:mockito-core:4.9.0")
-    testImplementation("com.google.guava:guava:31.1-jre")
+    testImplementation("org.mockito:mockito-core:4.11.0")
+    testImplementation("com.google.guava:guava:32.1.3-jre")
   }
 
   base {
-    archivesBaseName = "fluency"
+    archivesName.set("fluency")
   }
 
   java {
@@ -72,7 +72,7 @@ subprojects {
   tasks.withType<ShadowJar> {
     relocate("com.fasterxml.jackson", "org.komamitsu.thirdparty.jackson")
     relocate("org.msgpack.jackson", "org.komamitsu.thirdparty.msgpack.jackson")
-    classifier = "shadow"
+    archiveClassifier.set("shadow")
   }
 
   publishing {
@@ -170,8 +170,8 @@ subprojects {
     }
 
     reports {
-      xml.isEnabled = true
-      html.isEnabled = true
+      xml.required.set(true)
+      html.required.set(true)
     }
   }
 
diff --git a/fluency-aws-s3/build.gradle.kts b/fluency-aws-s3/build.gradle.kts
index e57cd17a..6119e1ae 100644
--- a/fluency-aws-s3/build.gradle.kts
+++ b/fluency-aws-s3/build.gradle.kts
@@ -1,5 +1,5 @@
 dependencies {
   implementation(projects.fluencyCore)
 
-  implementation("software.amazon.awssdk:s3:2.18.24")
+  implementation("software.amazon.awssdk:s3:2.21.27")
 }
diff --git a/fluency-treasuredata/src/main/java/org/komamitsu/fluency/treasuredata/ingester/sender/TreasureDataSender.java b/fluency-treasuredata/src/main/java/org/komamitsu/fluency/treasuredata/ingester/sender/TreasureDataSender.java
index e4bb720e..9457fa22 100644
--- a/fluency-treasuredata/src/main/java/org/komamitsu/fluency/treasuredata/ingester/sender/TreasureDataSender.java
+++ b/fluency-treasuredata/src/main/java/org/komamitsu/fluency/treasuredata/ingester/sender/TreasureDataSender.java
@@ -17,7 +17,6 @@
 package org.komamitsu.fluency.treasuredata.ingester.sender;
 
 import com.fasterxml.jackson.databind.util.ByteBufferBackedInputStream;
-import com.google.common.annotations.VisibleForTesting;
 import com.treasuredata.client.TDClient;
 import com.treasuredata.client.TDClientBuilder;
 import com.treasuredata.client.TDClientHttpException;
@@ -31,6 +30,7 @@
 import org.komamitsu.fluency.validation.Validatable;
 import org.komamitsu.fluency.validation.annotation.DecimalMin;
 import org.komamitsu.fluency.validation.annotation.Min;
+import org.msgpack.core.annotations.VisibleForTesting;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index ae04661e..e411586a 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.5.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists