diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 7c4c30b..7219fb2 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -3,9 +3,9 @@ autoService = "1.0"
 gjf = "1.11.0"
 jvmTarget = "1.8"
 kotlin = "1.6.10"
-kotlinCompileTesting = "1.4.6"
+kotlinCompileTesting = "1.4.7"
 kotlinpoet = "1.10.2"
-ksp = "1.6.0-1.0.1"
+ksp = "1.6.10-1.0.2"
 ktlint = "0.41.0"
 
 [plugins]
@@ -14,7 +14,7 @@ japicmp = { id = "me.champeau.gradle.japicmp", version = "0.2.9" }
 ksp = { id = "com.google.devtools.ksp", version.ref = "ksp" }
 mavenPublish = { id = "com.vanniktech.maven.publish", version = "0.18.0" }
 mavenShadow = { id = "com.github.johnrengelman.shadow", version = "7.0.0" }
-spotless = { id = "com.diffplug.spotless", version = "5.14.2" }
+spotless = { id = "com.diffplug.spotless", version = "6.1.0" }
 
 [libraries]
 asm = "org.ow2.asm:asm:9.2"
@@ -31,7 +31,7 @@ kotlinpoet-ksp = { module = "com.squareup:kotlinpoet-ksp", version.ref = "kotlin
 kotlinxMetadata = "org.jetbrains.kotlinx:kotlinx-metadata-jvm:0.4.0"
 ksp = { module = "com.google.devtools.ksp:symbol-processing", version.ref = "ksp" }
 ksp-api = { module = "com.google.devtools.ksp:symbol-processing-api", version.ref = "ksp" }
-okio = "com.squareup.okio:okio:2.10.0"
+okio = "com.squareup.okio:okio:3.0.0"
 
 # Test libs
 assertj = "org.assertj:assertj-core:3.11.1"
diff --git a/moshi-kotlin-codegen/src/test/java/com/squareup/moshi/kotlin/codegen/apt/JsonClassCodegenProcessorTest.kt b/moshi-kotlin-codegen/src/test/java/com/squareup/moshi/kotlin/codegen/apt/JsonClassCodegenProcessorTest.kt
index e5bbba6..afc875d 100644
--- a/moshi-kotlin-codegen/src/test/java/com/squareup/moshi/kotlin/codegen/apt/JsonClassCodegenProcessorTest.kt
+++ b/moshi-kotlin-codegen/src/test/java/com/squareup/moshi/kotlin/codegen/apt/JsonClassCodegenProcessorTest.kt
@@ -39,7 +39,7 @@ import kotlin.reflect.full.declaredMemberProperties
 /** Execute kotlinc to confirm that either files are generated or errors are printed. */
 class JsonClassCodegenProcessorTest {
 
-  @Rule @JvmField var temporaryFolder: TemporaryFolder = TemporaryFolder()
+  @Rule @JvmField val temporaryFolder: TemporaryFolder = TemporaryFolder()
 
   @Test
   fun privateConstructor() {
diff --git a/moshi-kotlin-codegen/src/test/java/com/squareup/moshi/kotlin/codegen/ksp/JsonClassSymbolProcessorTest.kt b/moshi-kotlin-codegen/src/test/java/com/squareup/moshi/kotlin/codegen/ksp/JsonClassSymbolProcessorTest.kt
index 17732d7..01930f1 100644
--- a/moshi-kotlin-codegen/src/test/java/com/squareup/moshi/kotlin/codegen/ksp/JsonClassSymbolProcessorTest.kt
+++ b/moshi-kotlin-codegen/src/test/java/com/squareup/moshi/kotlin/codegen/ksp/JsonClassSymbolProcessorTest.kt
@@ -34,7 +34,7 @@ import org.junit.rules.TemporaryFolder
 /** Execute kotlinc to confirm that either files are generated or errors are printed. */
 class JsonClassSymbolProcessorTest {
 
-  @Rule @JvmField var temporaryFolder: TemporaryFolder = TemporaryFolder()
+  @Rule @JvmField val temporaryFolder: TemporaryFolder = TemporaryFolder()
 
   @Test
   fun privateConstructor() {
diff --git a/moshi-kotlin/src/main/java/com/squareup/moshi/KotlinJsonAdapter.kt b/moshi-kotlin/src/main/java/com/squareup/moshi/KotlinJsonAdapterFactory.kt
similarity index 100%
rename from moshi-kotlin/src/main/java/com/squareup/moshi/KotlinJsonAdapter.kt
rename to moshi-kotlin/src/main/java/com/squareup/moshi/KotlinJsonAdapterFactory.kt
diff --git a/moshi-kotlin/src/main/java/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapter.kt b/moshi-kotlin/src/main/java/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapterFactory.kt
similarity index 100%
rename from moshi-kotlin/src/main/java/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapter.kt
rename to moshi-kotlin/src/main/java/com/squareup/moshi/kotlin/reflect/KotlinJsonAdapterFactory.kt
diff --git a/moshi/build.gradle.kts b/moshi/build.gradle.kts
index 3d638f2..c4e1f08 100644
--- a/moshi/build.gradle.kts
+++ b/moshi/build.gradle.kts
@@ -60,7 +60,11 @@ tasks.withType<Test>().configureEach {
 tasks.withType<KotlinCompile>()
   .configureEach {
     kotlinOptions {
-      val toAdd = mutableListOf("-Xopt-in=kotlin.RequiresOptIn", "-Xopt-in=kotlin.contracts.ExperimentalContracts")
+      val toAdd = mutableListOf(
+        "-Xopt-in=kotlin.RequiresOptIn",
+        "-Xopt-in=kotlin.contracts.ExperimentalContracts",
+        "-Xjvm-default=enable"
+      )
       if (name.contains("test", true)) {
         toAdd += "-Xopt-in=kotlin.ExperimentalStdlibApi"
       }