diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ddbed93a0..fffff4a57 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,7 +16,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        kotlin-version: [ 1.9.24 ]
+        kotlin-version: [ 2.0.21 ]
 
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
@@ -36,7 +36,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        kotlin-version: [ 1.9.24 ]
+        kotlin-version: [ 2.0.21 ]
 
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
@@ -162,8 +162,8 @@ jobs:
       # solution.
       fail-fast: false
       matrix:
-        kotlin-version: [ 1.9.24 ]
-        agp-version: [ 7.1.1, 7.2.0, 7.3.1 ]
+        kotlin-version: [ 2.0.21 ]
+        agp-version: [ 7.2.0, 7.3.1 ]
 
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
@@ -194,7 +194,7 @@ jobs:
       # solution.
       fail-fast: false
       matrix:
-        kotlin-version: [ 1.9.24 ]
+        kotlin-version: [ 2.0.21 ]
 
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
diff --git a/annotations-optional/dependencies/runtimeClasspath.txt b/annotations-optional/dependencies/runtimeClasspath.txt
index 838ee9d83..b4f3e56ab 100644
--- a/annotations-optional/dependencies/runtimeClasspath.txt
+++ b/annotations-optional/dependencies/runtimeClasspath.txt
@@ -1,3 +1,3 @@
 javax.inject:javax.inject:1
-org.jetbrains.kotlin:kotlin-stdlib:1.9.24
+org.jetbrains.kotlin:kotlin-stdlib:2.0.21
 org.jetbrains:annotations:13.0
diff --git a/annotations/dependencies/runtimeClasspath.txt b/annotations/dependencies/runtimeClasspath.txt
index ecec3fda5..8b9b920b5 100644
--- a/annotations/dependencies/runtimeClasspath.txt
+++ b/annotations/dependencies/runtimeClasspath.txt
@@ -1,2 +1,2 @@
-org.jetbrains.kotlin:kotlin-stdlib:1.9.24
+org.jetbrains.kotlin:kotlin-stdlib:2.0.21
 org.jetbrains:annotations:13.0
diff --git a/build-logic/conventions/src/main/kotlin/com/squareup/anvil/conventions/BasePlugin.kt b/build-logic/conventions/src/main/kotlin/com/squareup/anvil/conventions/BasePlugin.kt
index 710ca7e91..7ef8e6414 100644
--- a/build-logic/conventions/src/main/kotlin/com/squareup/anvil/conventions/BasePlugin.kt
+++ b/build-logic/conventions/src/main/kotlin/com/squareup/anvil/conventions/BasePlugin.kt
@@ -108,6 +108,11 @@ abstract class BasePlugin : Plugin<Project> {
         }
 
         freeCompilerArgs.addAll(extension.kotlinCompilerArgs.get())
+        // We do not yet support K2, and KAPT + Kotlin 2.0 generates a warning about falling back to
+        // language version 1.9. Because we treat all warnings as errors, we need to suppress this
+        // specific warning to not fail the build. Related YT ticket:
+        // https://youtrack.jetbrains.com/issue/KT-68400/K2-w-Kapt-currently-doesnt-support-language-version-2.0.-Falling-back-to-1.9.
+        freeCompilerArgs.add("-Xsuppress-version-warnings")
 
         fun isTestSourceSet(): Boolean {
           val regex = """(?:gradle|Unit|[aA]ndroid)Test""".toRegex()
diff --git a/compiler-api/dependencies/runtimeClasspath.txt b/compiler-api/dependencies/runtimeClasspath.txt
index ab38ea102..750bcfd16 100644
--- a/compiler-api/dependencies/runtimeClasspath.txt
+++ b/compiler-api/dependencies/runtimeClasspath.txt
@@ -1,8 +1,9 @@
 org.jetbrains.intellij.deps:trove4j:1.0.20200330
-org.jetbrains.kotlin:kotlin-bom:1.9.24
-org.jetbrains.kotlin:kotlin-compiler-embeddable:1.9.24
-org.jetbrains.kotlin:kotlin-daemon-embeddable:1.9.24
-org.jetbrains.kotlin:kotlin-reflect:1.9.24
-org.jetbrains.kotlin:kotlin-script-runtime:1.9.24
-org.jetbrains.kotlin:kotlin-stdlib:1.9.24
+org.jetbrains.kotlin:kotlin-bom:2.0.21
+org.jetbrains.kotlin:kotlin-compiler-embeddable:2.0.21
+org.jetbrains.kotlin:kotlin-daemon-embeddable:2.0.21
+org.jetbrains.kotlin:kotlin-reflect:2.0.21
+org.jetbrains.kotlin:kotlin-script-runtime:2.0.21
+org.jetbrains.kotlin:kotlin-stdlib:2.0.21
+org.jetbrains.kotlinx:kotlinx-coroutines-core-jvm:1.6.4
 org.jetbrains:annotations:13.0
diff --git a/compiler-api/src/main/java/com/squareup/anvil/compiler/api/AnvilCompilationException.kt b/compiler-api/src/main/java/com/squareup/anvil/compiler/api/AnvilCompilationException.kt
index 94eaa82ac..55162aec7 100644
--- a/compiler-api/src/main/java/com/squareup/anvil/compiler/api/AnvilCompilationException.kt
+++ b/compiler-api/src/main/java/com/squareup/anvil/compiler/api/AnvilCompilationException.kt
@@ -12,6 +12,7 @@ import org.jetbrains.kotlin.descriptors.annotations.AnnotationDescriptor
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
+import org.jetbrains.kotlin.ir.symbols.UnsafeDuringIrConstructionAPI
 import org.jetbrains.kotlin.ir.util.render
 import org.jetbrains.kotlin.js.resolve.diagnostics.findPsi
 import org.jetbrains.kotlin.resolve.source.KotlinSourceElement
@@ -114,6 +115,7 @@ public class AnvilCompilationException(
       message: String,
       cause: Throwable? = null,
     ): AnvilCompilationException {
+      @OptIn(UnsafeDuringIrConstructionAPI::class)
       return AnvilCompilationException(
         message = message,
         cause = cause,
diff --git a/compiler-utils/dependencies/runtimeClasspath.txt b/compiler-utils/dependencies/runtimeClasspath.txt
index 1f0b5b680..5fcc1ddcb 100644
--- a/compiler-utils/dependencies/runtimeClasspath.txt
+++ b/compiler-utils/dependencies/runtimeClasspath.txt
@@ -1,12 +1,14 @@
-com.google.dagger:dagger:2.51.1
-com.squareup:kotlinpoet-jvm:1.16.0
-com.squareup:kotlinpoet:1.16.0
+com.google.dagger:dagger:2.52
+com.squareup:kotlinpoet-jvm:1.18.1
+com.squareup:kotlinpoet:1.18.1
+jakarta.inject:jakarta.inject-api:2.0.1
 javax.inject:javax.inject:1
 org.jetbrains.intellij.deps:trove4j:1.0.20200330
-org.jetbrains.kotlin:kotlin-bom:1.9.24
-org.jetbrains.kotlin:kotlin-compiler-embeddable:1.9.24
-org.jetbrains.kotlin:kotlin-daemon-embeddable:1.9.24
-org.jetbrains.kotlin:kotlin-reflect:1.9.24
-org.jetbrains.kotlin:kotlin-script-runtime:1.9.24
-org.jetbrains.kotlin:kotlin-stdlib:1.9.24
+org.jetbrains.kotlin:kotlin-bom:2.0.21
+org.jetbrains.kotlin:kotlin-compiler-embeddable:2.0.21
+org.jetbrains.kotlin:kotlin-daemon-embeddable:2.0.21
+org.jetbrains.kotlin:kotlin-reflect:2.0.21
+org.jetbrains.kotlin:kotlin-script-runtime:2.0.21
+org.jetbrains.kotlin:kotlin-stdlib:2.0.21
+org.jetbrains.kotlinx:kotlinx-coroutines-core-jvm:1.6.4
 org.jetbrains:annotations:13.0
diff --git a/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/AnvilCompilation.kt b/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/AnvilCompilation.kt
index 34ea24331..a4086b76a 100644
--- a/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/AnvilCompilation.kt
+++ b/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/AnvilCompilation.kt
@@ -20,6 +20,7 @@ import dagger.internal.codegen.ComponentProcessor
 import dagger.internal.codegen.KspComponentProcessor
 import org.intellij.lang.annotations.Language
 import org.jetbrains.kotlin.config.JvmTarget
+import org.jetbrains.kotlin.config.LanguageVersion
 import java.io.File
 import java.io.OutputStream
 import java.nio.file.Files
@@ -46,7 +47,7 @@ public class AnvilCompilation internal constructor(
     disableComponentMerging: Boolean = false,
     enableExperimentalAnvilApis: Boolean = true,
     trackSourceFiles: Boolean = true,
-    mode: AnvilCompilationMode = Embedded(emptyList()),
+    mode: AnvilCompilationMode = Embedded(),
     enableAnvil: Boolean = true,
   ): AnvilCompilation = apply {
     checkNotCompiled()
@@ -306,7 +307,7 @@ public fun compileAnvil(
   enableExperimentalAnvilApis: Boolean = true,
   trackSourceFiles: Boolean = true,
   previousCompilationResult: JvmCompilationResult? = null,
-  mode: AnvilCompilationMode = Embedded(emptyList()),
+  mode: AnvilCompilationMode = Embedded(),
   moduleName: String? = null,
   jvmTarget: JvmTarget? = null,
   expectExitCode: KotlinCompilation.ExitCode? = null,
@@ -315,6 +316,8 @@ public fun compileAnvil(
   return AnvilCompilation()
     .apply {
       kotlinCompilation.apply {
+        languageVersion = LanguageVersion.KOTLIN_1_9.versionString
+        apiVersion = LanguageVersion.KOTLIN_1_9.versionString
         this.allWarningsAsErrors = allWarningsAsErrors
         this.messageOutputStream = messageOutputStream
         if (workingDir != null) {
diff --git a/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/AnvilCompilationMode.kt b/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/AnvilCompilationMode.kt
index 9bd888415..d253afabd 100644
--- a/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/AnvilCompilationMode.kt
+++ b/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/AnvilCompilationMode.kt
@@ -9,7 +9,6 @@ import com.squareup.anvil.compiler.api.CodeGenerator
 public sealed class AnvilCompilationMode(public val analysisBackend: AnalysisBackend) {
   public data class Embedded(
     val codeGenerators: List<CodeGenerator> = emptyList(),
-    val useDagger: Boolean = false,
   ) : AnvilCompilationMode(EMBEDDED)
   public data class Ksp(
     val symbolProcessorProviders: List<SymbolProcessorProvider> = emptyList(),
diff --git a/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/TestUtils.kt b/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/TestUtils.kt
index aded1f261..7ddc4e865 100644
--- a/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/TestUtils.kt
+++ b/compiler-utils/src/testFixtures/java/com/squareup/anvil/compiler/internal/testing/TestUtils.kt
@@ -11,7 +11,7 @@ import dagger.Component
 import dagger.Module
 import dagger.Provides
 import dagger.Subcomponent
-import org.jetbrains.kotlin.analysis.utils.collections.mapToSet
+import org.jetbrains.kotlin.utils.mapToSetOrEmpty
 import kotlin.reflect.KClass
 
 @ExperimentalAnvilApi
@@ -29,7 +29,7 @@ public fun Class<*>.moduleFactoryClass(
 
   val providesMethods = methodsOrCompanionMethods
     .filter { it.isAnnotationPresent(Provides::class.java) }
-    .mapToSet { it.name }
+    .mapToSetOrEmpty { it.name }
 
   assertWithMessage("No @Provides methods found in $this")
     .that(providesMethods)
diff --git a/compiler/dependencies/runtimeClasspath.txt b/compiler/dependencies/runtimeClasspath.txt
index f34ff5d9a..eb6147190 100644
--- a/compiler/dependencies/runtimeClasspath.txt
+++ b/compiler/dependencies/runtimeClasspath.txt
@@ -1,14 +1,16 @@
-com.google.dagger:dagger:2.51.1
-com.squareup:kotlinpoet-jvm:1.16.0
-com.squareup:kotlinpoet-ksp:1.16.0
-com.squareup:kotlinpoet:1.16.0
+com.google.dagger:dagger:2.52
+com.squareup:kotlinpoet-jvm:1.18.1
+com.squareup:kotlinpoet-ksp:1.18.1
+com.squareup:kotlinpoet:1.18.1
+jakarta.inject:jakarta.inject-api:2.0.1
 javax.annotation:jsr250-api:1.0
 javax.inject:javax.inject:1
 org.jetbrains.intellij.deps:trove4j:1.0.20200330
-org.jetbrains.kotlin:kotlin-bom:1.9.24
-org.jetbrains.kotlin:kotlin-compiler-embeddable:1.9.24
-org.jetbrains.kotlin:kotlin-daemon-embeddable:1.9.24
-org.jetbrains.kotlin:kotlin-reflect:1.9.24
-org.jetbrains.kotlin:kotlin-script-runtime:1.9.24
-org.jetbrains.kotlin:kotlin-stdlib:1.9.24
+org.jetbrains.kotlin:kotlin-bom:2.0.21
+org.jetbrains.kotlin:kotlin-compiler-embeddable:2.0.21
+org.jetbrains.kotlin:kotlin-daemon-embeddable:2.0.21
+org.jetbrains.kotlin:kotlin-reflect:2.0.21
+org.jetbrains.kotlin:kotlin-script-runtime:2.0.21
+org.jetbrains.kotlin:kotlin-stdlib:2.0.21
+org.jetbrains.kotlinx:kotlinx-coroutines-core-jvm:1.6.4
 org.jetbrains:annotations:13.0
diff --git a/compiler/src/main/java/com/squareup/anvil/compiler/IrContributionMerger.kt b/compiler/src/main/java/com/squareup/anvil/compiler/IrContributionMerger.kt
index c4b0d0cb6..e432e9d1f 100644
--- a/compiler/src/main/java/com/squareup/anvil/compiler/IrContributionMerger.kt
+++ b/compiler/src/main/java/com/squareup/anvil/compiler/IrContributionMerger.kt
@@ -26,6 +26,7 @@ import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
 import org.jetbrains.kotlin.ir.expressions.IrConstructorCall
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrVararg
+import org.jetbrains.kotlin.ir.symbols.UnsafeDuringIrConstructionAPI
 import org.jetbrains.kotlin.ir.types.classFqName
 import org.jetbrains.kotlin.ir.types.classOrFail
 import org.jetbrains.kotlin.ir.types.classOrNull
@@ -49,6 +50,7 @@ import java.io.File
  * as super types to Dagger components annotated with `@MergeComponent` or `@MergeSubcomponent`.
  * This also supports arbitrary interface merging on interfaces annotated with `@MergeInterfaces`.
  */
+@OptIn(org.jetbrains.kotlin.backend.common.extensions.FirIncompatiblePluginAPI::class)
 internal class IrContributionMerger(
   private val classScanner: ClassScanner,
   private val moduleDescriptorFactory: RealAnvilModuleDescriptor.Factory,
@@ -160,6 +162,7 @@ internal class IrContributionMerger(
     irMergesFile.writeText(mergedText)
   }
 
+  @OptIn(UnsafeDuringIrConstructionAPI::class)
   private fun IrBuilderWithScope.addMergedModules(
     annotations: List<AnnotationReferenceIr>,
     moduleFragment: IrModuleFragment,
@@ -378,6 +381,7 @@ internal class IrContributionMerger(
     contributedModules: Sequence<IrClass>,
     annotations: List<AnnotationReferenceIr>,
   ): IrConstructorCall {
+    @OptIn(UnsafeDuringIrConstructionAPI::class)
     return irCallConstructor(
       callee = pluginContext
         .referenceConstructors(daggerAnnotationFqName.classIdBestGuess())
@@ -628,6 +632,7 @@ internal class IrContributionMerger(
 
     // Since we are modifying the state of the code here, this does not need to be reflected in
     // the associated [ClassReferenceIr] which is more of an initial snapshot.
+    @OptIn(UnsafeDuringIrConstructionAPI::class)
     clazz.owner.superTypes += toAdd
 
     // Return the list of added supertypes
diff --git a/compiler/src/main/java/com/squareup/anvil/compiler/IrUtils.kt b/compiler/src/main/java/com/squareup/anvil/compiler/IrUtils.kt
index 084d1523f..9480be202 100644
--- a/compiler/src/main/java/com/squareup/anvil/compiler/IrUtils.kt
+++ b/compiler/src/main/java/com/squareup/anvil/compiler/IrUtils.kt
@@ -10,6 +10,7 @@ import org.jetbrains.kotlin.ir.declarations.IrDeclarationWithName
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.IrClassifierSymbol
+import org.jetbrains.kotlin.ir.symbols.UnsafeDuringIrConstructionAPI
 import org.jetbrains.kotlin.ir.types.IrSimpleType
 import org.jetbrains.kotlin.ir.types.classifierOrNull
 import org.jetbrains.kotlin.ir.types.typeOrNull
@@ -38,6 +39,7 @@ internal fun IrClass.requireClassId(): ClassId {
   )
 }
 
+@OptIn(UnsafeDuringIrConstructionAPI::class)
 internal fun IrClassSymbol.requireClassId(): ClassId = owner.requireClassId()
 
 internal val IrExpression.kclassUnwrapped: IrClassifierSymbol
@@ -53,6 +55,7 @@ internal val IrDeclarationWithName.fqName: FqName
     element = this,
   )
 
+@OptIn(UnsafeDuringIrConstructionAPI::class)
 internal val IrClassSymbol.fqName: FqName get() = owner.fqName
 
 // If we're evaluating an anonymous inner class, it cannot merge anything and will cause
diff --git a/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/AnnotationArgumentReferenceIr.kt b/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/AnnotationArgumentReferenceIr.kt
index e34695edb..2769578ef 100644
--- a/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/AnnotationArgumentReferenceIr.kt
+++ b/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/AnnotationArgumentReferenceIr.kt
@@ -7,6 +7,7 @@ import org.jetbrains.kotlin.ir.declarations.IrValueParameter
 import org.jetbrains.kotlin.ir.expressions.IrConst
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrVararg
+import org.jetbrains.kotlin.ir.symbols.UnsafeDuringIrConstructionAPI
 import kotlin.LazyThreadSafetyMode.NONE
 
 internal class AnnotationArgumentReferenceIr(
@@ -25,6 +26,7 @@ internal class AnnotationArgumentReferenceIr(
 
   // We currently special-case for Classes, but this is the spot we'll need to update if we need to
   // support primitives later on.
+  @OptIn(UnsafeDuringIrConstructionAPI::class)
   private fun findValue(): Any {
     (argumentExpression as? IrConst<*>)?.let {
       return it.value as Any
diff --git a/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/AnnotationReferenceIr.kt b/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/AnnotationReferenceIr.kt
index 9d725a3dc..683848c95 100644
--- a/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/AnnotationReferenceIr.kt
+++ b/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/AnnotationReferenceIr.kt
@@ -4,6 +4,7 @@ import com.squareup.anvil.compiler.api.AnvilCompilationException
 import com.squareup.anvil.compiler.internal.reference.AnnotationReference
 import org.jetbrains.kotlin.backend.common.extensions.IrPluginContext
 import org.jetbrains.kotlin.ir.expressions.IrConstructorCall
+import org.jetbrains.kotlin.ir.symbols.UnsafeDuringIrConstructionAPI
 import org.jetbrains.kotlin.ir.util.getArgumentsWithIr
 import org.jetbrains.kotlin.ir.util.parentAsClass
 import org.jetbrains.kotlin.name.FqName
@@ -83,6 +84,7 @@ internal class AnnotationReferenceIr(
   }
 }
 
+@OptIn(UnsafeDuringIrConstructionAPI::class)
 internal fun IrConstructorCall.toAnnotationReference(
   context: IrPluginContext,
   declaringClass: ClassReferenceIr?,
diff --git a/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/ClassReferenceIr.kt b/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/ClassReferenceIr.kt
index 3eddd1a5a..a3ebb9cad 100644
--- a/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/ClassReferenceIr.kt
+++ b/compiler/src/main/java/com/squareup/anvil/compiler/codegen/reference/ClassReferenceIr.kt
@@ -13,12 +13,15 @@ import org.jetbrains.kotlin.backend.common.lower.parents
 import org.jetbrains.kotlin.descriptors.DescriptorVisibilities
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
+import org.jetbrains.kotlin.ir.symbols.UnsafeDuringIrConstructionAPI
 import org.jetbrains.kotlin.ir.util.isInterface
 import org.jetbrains.kotlin.ir.util.packageFqName
+import org.jetbrains.kotlin.ir.util.parents
 import org.jetbrains.kotlin.name.ClassId
 import org.jetbrains.kotlin.name.FqName
 import kotlin.LazyThreadSafetyMode.NONE
 
+@OptIn(UnsafeDuringIrConstructionAPI::class)
 internal class ClassReferenceIr(
   val clazz: IrClassSymbol,
   val context: IrPluginContext,
@@ -31,6 +34,7 @@ internal class ClassReferenceIr(
     get() = fqName.shortName().asString()
 
   val enclosingClassesWithSelf: List<ClassReferenceIr> by lazy {
+    @OptIn(UnsafeDuringIrConstructionAPI::class)
     clazz.owner.parents
       .filterIsInstance<IrClass>()
       .map { it.symbol.toClassReference(context) }
diff --git a/gradle-plugin/dependencies/runtimeClasspath.txt b/gradle-plugin/dependencies/runtimeClasspath.txt
index ecec3fda5..8b9b920b5 100644
--- a/gradle-plugin/dependencies/runtimeClasspath.txt
+++ b/gradle-plugin/dependencies/runtimeClasspath.txt
@@ -1,2 +1,2 @@
-org.jetbrains.kotlin:kotlin-stdlib:1.9.24
+org.jetbrains.kotlin:kotlin-stdlib:2.0.21
 org.jetbrains:annotations:13.0
diff --git a/gradle-plugin/src/main/java/com/squareup/anvil/plugin/AnvilPlugin.kt b/gradle-plugin/src/main/java/com/squareup/anvil/plugin/AnvilPlugin.kt
index c23d45781..1bf074f73 100644
--- a/gradle-plugin/src/main/java/com/squareup/anvil/plugin/AnvilPlugin.kt
+++ b/gradle-plugin/src/main/java/com/squareup/anvil/plugin/AnvilPlugin.kt
@@ -113,15 +113,21 @@ internal open class AnvilPlugin : KotlinCompilerPluginSupportPlugin {
   override fun applyToCompilation(
     kotlinCompilation: KotlinCompilation<*>,
   ): Provider<List<SubpluginOption>> {
-    kotlinCompilation.compilerOptions.options.let {
-      @Suppress("DEPRECATION")
-      val useK2 = it.useK2.get()
-      if (useK2 || it.languageVersion.getOrElse(KOTLIN_1_9) >= KOTLIN_2_0) {
-        kotlinCompilation.project.logger
-          .error(
-            "NOTE: Anvil is currently incompatible with the K2 compiler. Related GH issue:" +
-              "https://github.com/square/anvil/issues/733",
-          )
+    kotlinCompilation.compileTaskProvider.configure { action ->
+      action.compilerOptions.let {
+        @Suppress("DEPRECATION")
+        val useK2 = it.useK2.get()
+        if (useK2 || it.languageVersion.getOrElse(KOTLIN_1_9) >= KOTLIN_2_0) {
+          kotlinCompilation.project.logger
+            .warn(
+              "NOTE: Anvil is currently incompatible with the K2 compiler and the language " +
+                "version will be overridden to 1.9. Related GH issue:" +
+                "https://github.com/square/anvil/issues/733",
+            )
+        }
+
+        it.languageVersion.set(org.jetbrains.kotlin.gradle.dsl.KotlinVersion.KOTLIN_1_9)
+        it.apiVersion.set(org.jetbrains.kotlin.gradle.dsl.KotlinVersion.KOTLIN_1_9)
       }
     }
 
diff --git a/gradle.properties b/gradle.properties
index ff7a05276..81bd3a8b7 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -49,3 +49,5 @@ android.defaults.buildfeatures.viewBinding=false
 
 # Suppress the warning about MPP being in alpha.
 kotlin.mpp.stability.nowarn=true
+
+kotlin.languageVersion=1.9
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 0d1a6aabd..ad8d970a8 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -19,7 +19,7 @@ autoService = "1.1.1"
 autoValue = "1.11.0"
 buildconfig = "5.4.0"
 classgraph = "4.8.174"
-dagger = "2.51.1"
+dagger = "2.52"
 dropbox-dependencyGuard = "0.5.0"
 dokka = "1.9.20"
 espresso = "3.5.1"
@@ -29,14 +29,14 @@ jvm-toolchain = "17"
 jvm-target-library = "8"
 jvm-target-minimal = "11"
 kase = "0.11.1"
-kct = "0.4.0"
+kct = "0.5.1"
 kgx = "0.1.12"
 kotest = "5.9.1"
-kotlin = "1.9.24"
+kotlin = "2.0.21"
 kotlinx-binaryCompatibility = "0.16.2"
-kotlinpoet = "1.16.0"
+kotlinpoet = "1.18.1"
 # If updating KSP version, we currently have ksp override logic in settings.gradle that needs to be updated too
-ksp = "1.9.24-1.0.20"
+ksp = "2.0.21-1.0.25"
 ktlint = "1.0.1"
 ktlintPlugin = "12.1.1"
 mavenPublish = "0.29.0"