diff --git a/android/build.gradle b/android/build.gradle
index 07e6c4c..9feeae9 100644
--- a/android/build.gradle
+++ b/android/build.gradle
@@ -8,7 +8,7 @@ group='com.github.ivanisidrowu'
 
 android {
     compileSdkVersion 30
-    buildToolsVersion "30.0.0"
+    buildToolsVersion "30.0.3"
 
     defaultConfig {
         minSdkVersion 23
@@ -20,6 +20,11 @@ android {
         consumerProguardFiles "consumer-rules.pro"
     }
 
+    compileOptions {
+        sourceCompatibility 1.8
+        targetCompatibility 1.8
+    }
+
     buildTypes {
         release {
             minifyEnabled false
@@ -33,6 +38,10 @@ android {
                 '-Xopt-in=kotlinx.coroutines.ExperimentalCoroutinesApi',
         ]
     }
+
+    lintOptions {
+        abortOnError false
+    }
 }
 
 dependencies {
diff --git a/android/src/main/java/tw/ktrssreader/config/KtRssReaderConfig.kt b/android/src/main/java/tw/ktrssreader/config/KtRssReaderConfig.kt
index 50345e6..3716232 100644
--- a/android/src/main/java/tw/ktrssreader/config/KtRssReaderConfig.kt
+++ b/android/src/main/java/tw/ktrssreader/config/KtRssReaderConfig.kt
@@ -17,6 +17,7 @@
 package tw.ktrssreader.config
 
 import java.nio.charset.Charset
+import kotlin.time.Duration
 import kotlin.time.ExperimentalTime
 import kotlin.time.days
 
@@ -28,5 +29,5 @@ class KtRssReaderConfig {
     var flushCache: Boolean = false
 
     @ExperimentalTime
-    var expiredTimeMillis: Long = 1.days.toLongMilliseconds()
+    var expiredTimeMillis: Long = Duration.days(1).inWholeMilliseconds
 }
\ No newline at end of file
diff --git a/android/src/main/java/tw/ktrssreader/parser/AndroidParserBase.kt b/android/src/main/java/tw/ktrssreader/parser/AndroidParserBase.kt
index ef29f9a..806f7cb 100644
--- a/android/src/main/java/tw/ktrssreader/parser/AndroidParserBase.kt
+++ b/android/src/main/java/tw/ktrssreader/parser/AndroidParserBase.kt
@@ -151,7 +151,7 @@ abstract class AndroidParserBase<out T : RssStandardChannel> : tw.ktrssreader.ko
     }
 
     protected fun String.toBoolOrNull(): Boolean? {
-        return when (toLowerCase()) {
+        return when (lowercase()) {
             "yes", "true" -> true
             "no", "false" -> false
             else -> null
diff --git a/app/build.gradle b/app/build.gradle
index d0ac4f2..0336205 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -5,7 +5,7 @@ apply plugin: 'kotlin-kapt'
 
 android {
     compileSdkVersion 30
-    buildToolsVersion "30.0.0"
+    buildToolsVersion "30.0.3"
 
     defaultConfig {
         applicationId "tw.ktrssreader"
@@ -17,6 +17,11 @@ android {
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
 
+    compileOptions {
+        sourceCompatibility 1.8
+        targetCompatibility 1.8
+    }
+
     buildTypes {
         release {
             minifyEnabled false
diff --git a/build.gradle b/build.gradle
index 7af8c57..286a926 100644
--- a/build.gradle
+++ b/build.gradle
@@ -2,13 +2,13 @@
 buildscript {
 
     ext {
-        def coroutines_version = '1.3.9'
+        def coroutines_version = '1.5.0'
         def okhttp_version = '4.9.0'
-        def room_version = '2.2.5'
+        def room_version = '2.2.6'
         def startup_version = '1.0.0'
 
         def mockk_version = '1.10.0'
-        def turbine_version = '0.2.1'
+        def turbine_version = '0.5.0'
 
         deps = [
                 'kotlinxCoroutinesCore'   : "org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutines_version",
@@ -24,7 +24,7 @@ buildscript {
                 'turbine': "app.cash.turbine:turbine:$turbine_version"
         ]
 
-        kotlin_version = "1.4.0"
+        kotlin_version = "1.5.0"
     }
 
     repositories {
@@ -32,7 +32,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath "com.android.tools.build:gradle:4.0.1"
+        classpath "com.android.tools.build:gradle:4.1.3"
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath 'com.github.dcendents:android-maven-gradle-plugin:2.1'
 
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 74e0ad7..f705ea8 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.1.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
diff --git a/kotlin/src/main/java/tw/ktrssreader/kotlin/parser/ParserBase.kt b/kotlin/src/main/java/tw/ktrssreader/kotlin/parser/ParserBase.kt
index fecd2f6..3e49b77 100644
--- a/kotlin/src/main/java/tw/ktrssreader/kotlin/parser/ParserBase.kt
+++ b/kotlin/src/main/java/tw/ktrssreader/kotlin/parser/ParserBase.kt
@@ -247,7 +247,7 @@ abstract class ParserBase<out T : RssStandardChannel> : Parser<T> {
     }
 
     protected fun String.toBoolOrNull(): Boolean? {
-        return when (toLowerCase()) {
+        return when (lowercase()) {
             "yes", "true" -> true
             "no", "false" -> false
             else -> null
diff --git a/processor/src/main/java/tw/ktrssreader/processor/util/TypeExtensions.kt b/processor/src/main/java/tw/ktrssreader/processor/util/TypeExtensions.kt
index 7860ec4..8c9d2dd 100644
--- a/processor/src/main/java/tw/ktrssreader/processor/util/TypeExtensions.kt
+++ b/processor/src/main/java/tw/ktrssreader/processor/util/TypeExtensions.kt
@@ -45,22 +45,30 @@ fun String.isPrimitive(): Boolean = primitiveJavaPaths.any { this.contains(other
 fun String.getFuncName(): String {
     return when {
         this.startsWith(GOOGLE_PREFIX) || this.startsWith(ITUNES_PREFIX) ->
-            "get${this.substringAfterLast(':').capitalize(Locale.ROOT)}"
-        else -> "get${this.capitalize(Locale.ROOT)}"
+            "get${this.substringAfterLast(':').capitalize()}"
+        else -> "get${this.capitalize()}"
     }
 }
 
 fun String.getListFuncName(): String {
-    val tagCapitalized = substringAfterLast(':').capitalize(Locale.ROOT)
+    val tagCapitalized = substringAfterLast(':').capitalize()
     return when {
-        startsWith(GOOGLE_PREFIX) -> "get${GOOGLE_PREFIX.capitalize(Locale.ROOT)}${tagCapitalized}List"
-        startsWith(ITUNES_PREFIX) -> "get${ITUNES_PREFIX.capitalize(Locale.ROOT)}${tagCapitalized}List"
+        startsWith(GOOGLE_PREFIX) -> "get${GOOGLE_PREFIX.capitalize()}${tagCapitalized}List"
+        startsWith(ITUNES_PREFIX) -> "get${ITUNES_PREFIX.capitalize()}${tagCapitalized}List"
         else -> "get${tagCapitalized}List"
     }
 }
 
+internal fun String.capitalize(): String = replaceFirstChar {
+    if (it.isLowerCase()) {
+        it.titlecase(Locale.ROOT)
+    } else {
+        it.toString()
+    }
+}
+
 fun String.getGeneratedClassPath() =
-    "${GENERATOR_PACKAGE}.${this.capitalize(Locale.ROOT)}${PARSER_SUFFIX}"
+    "${GENERATOR_PACKAGE}.${this.capitalize()}${PARSER_SUFFIX}"
 
 fun String.extractListType() =
     this.substringAfter('<')
@@ -95,10 +103,10 @@ fun Element.getPackage(): String {
 }
 
 fun String.getVariableName(tag: String): String {
-    val tagCapitalized = tag.substringAfterLast(':').capitalize(Locale.ROOT)
+    val tagCapitalized = tag.substringAfterLast(':').capitalize()
     return when {
-        tag.startsWith(GOOGLE_PREFIX) -> "$this${GOOGLE_PREFIX.capitalize(Locale.ROOT)}$tagCapitalized"
-        tag.startsWith(ITUNES_PREFIX) -> "$this${ITUNES_PREFIX.capitalize(Locale.ROOT)}$tagCapitalized"
+        tag.startsWith(GOOGLE_PREFIX) -> "$this${GOOGLE_PREFIX.capitalize()}$tagCapitalized"
+        tag.startsWith(ITUNES_PREFIX) -> "$this${ITUNES_PREFIX.capitalize()}$tagCapitalized"
         else -> "$this$tagCapitalized"
     }
 }
@@ -126,7 +134,7 @@ fun Name.extractNameFromMethod(): String {
     }
 
     return withoutPrefix
-        .decapitalize(Locale.ROOT)
+        .replaceFirstChar { it.lowercase(Locale.ROOT) }
         .substringBeforeLast('$')
 }