diff --git a/compiler/cli/cli-js/src/org/jetbrains/kotlin/cli/js/K2JsIrCompiler.kt b/compiler/cli/cli-js/src/org/jetbrains/kotlin/cli/js/K2JsIrCompiler.kt
index 034c65393b7..ffffc4602bc 100644
--- a/compiler/cli/cli-js/src/org/jetbrains/kotlin/cli/js/K2JsIrCompiler.kt
+++ b/compiler/cli/cli-js/src/org/jetbrains/kotlin/cli/js/K2JsIrCompiler.kt
@@ -38,9 +38,7 @@ import org.jetbrains.kotlin.incremental.js.IncrementalDataProvider
 import org.jetbrains.kotlin.incremental.js.IncrementalNextRoundChecker
 import org.jetbrains.kotlin.incremental.js.IncrementalResultsConsumer
 import org.jetbrains.kotlin.ir.backend.js.*
-import org.jetbrains.kotlin.ir.backend.js.ic.actualizeCacheForModule
-import org.jetbrains.kotlin.ir.backend.js.ic.buildCache
-import org.jetbrains.kotlin.ir.backend.js.ic.checkCaches
+import org.jetbrains.kotlin.ir.backend.js.ic.*
 import org.jetbrains.kotlin.ir.declarations.impl.IrFactoryImpl
 import org.jetbrains.kotlin.ir.declarations.persistent.PersistentIrFactory
 import org.jetbrains.kotlin.js.analyzer.JsAnalysisResult
@@ -76,6 +74,10 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
     @Suppress("UNUSED_PARAMETER")
     private fun usePerFileInvalidator(configuration: CompilerConfiguration): Boolean = false
 
+    private fun IcCacheInfo.toICCacheMap(): Map<String, ICCache> {
+        return data.map { it.key to ICCache(PersistentCacheProvider.EMPTY, PersistentCacheConsumer.EMPTY, it.value) }.toMap()
+    }
+
     override fun doExecute(
         arguments: K2JSCompilerArguments,
         configuration: CompilerConfiguration,
@@ -234,7 +236,8 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
 
         // Run analysis if main module is sources
         lateinit var sourceModule: ModulesStructure
-        if (arguments.includes == null) {
+        val includes = arguments.includes
+        if (includes == null) {
             do {
                 sourceModule = prepareAnalyzedSourceModule(
                     projectJs,
@@ -245,7 +248,7 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
                     AnalyzerWithCompilerReport(config.configuration),
                     icUseGlobalSignatures = icCaches.isNotEmpty(),
                     icUseStdlibCache = icCaches.isNotEmpty(),
-                    icCache = if (icCaches.isNotEmpty()) checkCaches(libraries, icCaches, skipLib = arguments.includes).data else emptyMap()
+                    icCache = if (icCaches.isNotEmpty()) checkCaches(libraries, icCaches, skipLib = includes).toICCacheMap() else emptyMap()
                 )
                 val result = sourceModule.jsFrontEndResult.jsAnalysisResult
                 if (result is JsAnalysisResult.RetryWithAdditionalRoots) {
@@ -276,8 +279,6 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
 
             val phaseConfig = createPhaseConfig(jsPhases, arguments, messageCollector)
 
-            val includes = arguments.includes
-
             val module = if (includes != null) {
                 if (sourcesFiles.isNotEmpty()) {
                     messageCollector.report(ERROR, "Source files are not supported when -Xinclude is present")
@@ -294,7 +295,7 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
                     friendLibraries,
                     icUseGlobalSignatures = icCaches.isNotEmpty(),
                     icUseStdlibCache = icCaches.isNotEmpty(),
-                    icCache = if (icCaches.isNotEmpty()) checkCaches(libraries, icCaches, skipLib = includes).data else emptyMap()
+                    icCache = if (icCaches.isNotEmpty()) checkCaches(libraries, icCaches, skipLib = includes).toICCacheMap() else emptyMap()
                 )
             } else {
                 sourceModule
diff --git a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/fileUtil.kt b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/fileUtil.kt
index b1ad4bb631f..7517b9f83f7 100644
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/fileUtil.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/fileUtil.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.ir.backend.js.ic
 
 import com.intellij.openapi.project.Project
-import org.jetbrains.kotlin.analyzer.AbstractAnalyzerWithCompilerReport
 import org.jetbrains.kotlin.config.CompilerConfiguration
 import org.jetbrains.kotlin.ir.backend.js.MainModule
 import org.jetbrains.kotlin.ir.backend.js.toByteArray
@@ -20,6 +19,10 @@ import kotlin.random.nextULong
 // TODO: Proper version of the compiler (should take changes to lowerings into account)
 private val compilerVersion = Random.nextULong()
 
+private fun IcCacheInfo.toICCacheMap(): Map<String, ICCache> {
+    return data.map { it.key to ICCache(PersistentCacheProvider.EMPTY, PersistentCacheConsumer.EMPTY, it.value) }.toMap()
+}
+
 // TODO more parameters for lowerings
 // Returns true if caches were built. False if caches were up-to-date.
 fun buildCache(
@@ -50,9 +53,9 @@ fun buildCache(
     File(icDir, "info").delete()
     icDir.mkdirs()
 
-    val icData = prepareSingleLibraryIcCache(project, configuration, mainModule.libPath, dependencies, friendDependencies, exportedDeclarations, icCache.data)
+    val icData = prepareSingleLibraryIcCache(project, configuration, mainModule.libPath, dependencies, friendDependencies, exportedDeclarations, icCache.toICCacheMap())
 
-    icData.writeTo(File(cachePath))
+    icData.serializedIcData.writeTo(File(cachePath))
 
     CacheInfo(cachePath, mainModule.libPath, md5).save()
 
diff --git a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/ic.kt b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/ic.kt
index bbe7701b798..5cdb367416f 100644
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/ic.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/ic.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.ir.backend.js.ic
 
 import com.intellij.openapi.project.Project
-import org.jetbrains.kotlin.analyzer.AbstractAnalyzerWithCompilerReport
 import org.jetbrains.kotlin.backend.common.lower
 import org.jetbrains.kotlin.config.CompilerConfiguration
 import org.jetbrains.kotlin.ir.backend.js.*
@@ -34,8 +33,8 @@ fun prepareSingleLibraryIcCache(
     dependencies: Collection<String>,
     friendDependencies: Collection<String> = emptyList(),
     exportedDeclarations: Set<FqName> = emptySet(),
-    icCache: Map<String, SerializedIcData> = emptyMap(),
-): SerializedIcData {
+    icCache: Map<String, ICCache> = emptyMap(),
+): ICCache {
     val irFactory = PersistentIrFactory()
     val controller = WholeWorldStageController()
     irFactory.stageController = controller
@@ -67,13 +66,17 @@ fun prepareSingleLibraryIcCache(
 
     lowerPreservingIcData(moduleFragment, context, controller)
 
-    return IcSerializer(
-        context.irBuiltIns,
-        context.mapping,
-        irFactory,
-        deserializer,
-        moduleFragment
-    ).serializeDeclarations(irFactory.allDeclarations)
+    return ICCache(
+        PersistentCacheProvider.EMPTY,
+        PersistentCacheConsumer.EMPTY,
+        IcSerializer(
+            context.irBuiltIns,
+            context.mapping,
+            irFactory,
+            deserializer,
+            moduleFragment
+        ).serializeDeclarations(irFactory.allDeclarations)
+    )
 }
 
 private fun KotlinResolvedLibrary.allDependencies(): List<KotlinResolvedLibrary> {
diff --git a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/invalidation.kt b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/invalidation.kt
index 7d8ecd18d19..11a868bfd26 100644
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/invalidation.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/invalidation.kt
@@ -265,7 +265,8 @@ private fun createCacheConsumer(path: String): PersistentCacheConsumer {
 
 private fun loadCacheInfo(cachePaths: Collection<String>): MutableMap<ModulePath, String> {
     val caches = cachePaths.map { CacheInfo.load(it) ?: error("Cannot load IC cache from $it") }
-    return caches.associate { it.libPath.toCanonicalPath() to it.path } as MutableMap<ModulePath, String>
+    val result = mutableMapOf<ModulePath, String>()
+    return caches.associateTo(result) { it.libPath.toCanonicalPath() to it.path }
 }
 
 private fun loadLibraries(configuration: CompilerConfiguration, dependencies: Collection<String>): Map<ModulePath, KotlinLibrary> {
@@ -298,7 +299,7 @@ fun actualizeCacheForModule(
     val libraries: Map<ModulePath, KotlinLibrary> = loadLibraries(compilerConfiguration, dependencies)
 
     val persistentCacheProviders = icCacheMap.map { (lib, cache) ->
-        libraries[lib.toCanonicalPath()]!!.let { klib -> klib to createCacheProvider(cache) }
+        libraries[lib.toCanonicalPath()]!! to createCacheProvider(cache)
     }.toMap()
 
     val nameToKotlinLibrary: Map<ModuleName, KotlinLibrary> = libraries.values.associateBy { it.moduleName }
diff --git a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/klib.kt b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/klib.kt
index 1dac0d3674b..b437742cc72 100644
--- a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/klib.kt
+++ b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/klib.kt
@@ -30,6 +30,7 @@ import org.jetbrains.kotlin.descriptors.impl.ModuleDescriptorImpl
 import org.jetbrains.kotlin.incremental.components.LookupTracker
 import org.jetbrains.kotlin.ir.IrBuiltIns
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
+import org.jetbrains.kotlin.ir.backend.js.ic.ICCache
 import org.jetbrains.kotlin.ir.backend.js.ic.SerializedIcData
 import org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir.JsIrLinker
 import org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir.JsIrModuleSerializer
@@ -396,7 +397,7 @@ fun prepareAnalyzedSourceModule(
     analyzer: AbstractAnalyzerWithCompilerReport,
     icUseGlobalSignatures: Boolean = false,
     icUseStdlibCache: Boolean = false,
-    icCache: Map<String, SerializedIcData> = emptyMap(),
+    icCache: Map<String, ICCache> = emptyMap(),
     errorPolicy: ErrorTolerancePolicy = configuration.get(JSConfigurationKeys.ERROR_TOLERANCE_POLICY) ?: ErrorTolerancePolicy.DEFAULT,
 ): ModulesStructure {
     val mainModule = MainModule.SourceFiles(files)
@@ -490,12 +491,12 @@ class ModulesStructure(
     friendDependenciesPaths: Collection<String>,
     val icUseGlobalSignatures: Boolean,
     val icUseStdlibCache: Boolean,
-    val icCache: Map<String, SerializedIcData>,
+    val icCache: Map<String, ICCache>,
 ) {
     val loweringsCacheProvider: LoweringsCacheProvider = when {
         icUseStdlibCache -> object : LoweringsCacheProvider {
             override fun cacheByPath(path: String): SerializedIcData? {
-                return icCache[path]
+                return icCache[path]?.serializedIcData
             }
         }
         icUseGlobalSignatures -> EmptyLoweringsCacheProvider
diff --git a/js/js.tests/build.gradle.kts b/js/js.tests/build.gradle.kts
index a4c8064b591..fa94b68cec5 100644
--- a/js/js.tests/build.gradle.kts
+++ b/js/js.tests/build.gradle.kts
@@ -239,6 +239,7 @@ val testDataDir = project(":js:js.translator").projectDir.resolve("testData")
 
 projectTest(parallel = true) {
     setUpJsBoxTests(jsEnabled = true, jsIrEnabled = true)
+//    systemProperty("kotlin.js.ir.pir", "false")
 
     inputs.dir(rootDir.resolve("compiler/cli/cli-common/resources")) // compiler.xml
 
diff --git a/js/js.tests/test/org/jetbrains/kotlin/js/test/BasicBoxTest.kt b/js/js.tests/test/org/jetbrains/kotlin/js/test/BasicBoxTest.kt
index 35e7a07f413..ce237275470 100644
--- a/js/js.tests/test/org/jetbrains/kotlin/js/test/BasicBoxTest.kt
+++ b/js/js.tests/test/org/jetbrains/kotlin/js/test/BasicBoxTest.kt
@@ -19,7 +19,6 @@ import org.jetbrains.kotlin.cli.common.messages.AnalyzerWithCompilerReport
 import org.jetbrains.kotlin.cli.common.messages.MessageRenderer
 import org.jetbrains.kotlin.cli.common.messages.PrintingMessageCollector
 import org.jetbrains.kotlin.cli.common.output.writeAllTo
-import org.jetbrains.kotlin.cli.js.resolve
 import org.jetbrains.kotlin.cli.jvm.compiler.EnvironmentConfigFiles
 import org.jetbrains.kotlin.cli.jvm.compiler.KotlinCoreEnvironment
 import org.jetbrains.kotlin.config.*
@@ -27,7 +26,7 @@ import org.jetbrains.kotlin.idea.KotlinFileType
 import org.jetbrains.kotlin.incremental.js.IncrementalDataProviderImpl
 import org.jetbrains.kotlin.incremental.js.IncrementalResultsConsumerImpl
 import org.jetbrains.kotlin.incremental.js.TranslationResultValue
-import org.jetbrains.kotlin.ir.backend.js.ic.SerializedIcData
+import org.jetbrains.kotlin.ir.backend.js.ic.ICCache
 import org.jetbrains.kotlin.js.JavaScript
 import org.jetbrains.kotlin.js.backend.JsToStringGenerationVisitor
 import org.jetbrains.kotlin.js.backend.ast.*
@@ -36,7 +35,10 @@ import org.jetbrains.kotlin.js.dce.DeadCodeElimination
 import org.jetbrains.kotlin.js.dce.InputFile
 import org.jetbrains.kotlin.js.dce.InputResource
 import org.jetbrains.kotlin.js.engine.loadFiles
-import org.jetbrains.kotlin.js.facade.*
+import org.jetbrains.kotlin.js.facade.K2JSTranslator
+import org.jetbrains.kotlin.js.facade.MainCallParameters
+import org.jetbrains.kotlin.js.facade.TranslationResult
+import org.jetbrains.kotlin.js.facade.TranslationUnit
 import org.jetbrains.kotlin.js.parser.parse
 import org.jetbrains.kotlin.js.parser.sourcemaps.SourceMapError
 import org.jetbrains.kotlin.js.parser.sourcemaps.SourceMapLocationRemapper
@@ -178,6 +180,8 @@ abstract class BasicBoxTest(
                 return dependenciesSymbols.toSet() + dependenciesSymbols.flatMap { modules[it]!!.allTransitiveDependencies() }
             }
 
+            val checkIC = modules.any { it.value.hasFilesToRecompile }
+
             val orderedModules = DFS.topologicalOrder(modules.values) { module -> module.dependenciesSymbols.mapNotNull { modules[it] } }
 
             val testPackage = if (runPlainBoxFunction) null else testFactory.testPackage
@@ -191,7 +195,7 @@ abstract class BasicBoxTest(
             }
             val testModuleName = if (runPlainBoxFunction) null else mainModuleName
             val mainModule = modules[mainModuleName] ?: error("No module with name \"$mainModuleName\"")
-            val icCache = mutableMapOf<String, SerializedIcData>()
+            val icCache = mutableMapOf<String, ICCache>()
 
             val generatedJsFiles = orderedModules.asReversed().mapNotNull { module ->
                 val dependencies = module.dependenciesSymbols.map { modules[it]?.outputFileName(outputDir) + ".meta.js" }
@@ -233,6 +237,7 @@ abstract class BasicBoxTest(
                     safeExternalBooleanDiagnostic,
                     skipMangleVerification,
                     abiVersion,
+                    checkIC,
                     icCache
                 )
 
@@ -491,7 +496,8 @@ abstract class BasicBoxTest(
         safeExternalBooleanDiagnostic: RuntimeDiagnostic?,
         skipMangleVerification: Boolean,
         abiVersion: KotlinAbiVersion,
-        icCache: MutableMap<String, SerializedIcData>
+        checkIC: Boolean,
+        icCache: MutableMap<String, ICCache>
     ) {
         val kotlinFiles = module.files.filter { it.fileName.endsWith(".kt") }
         val testFiles = kotlinFiles.map { it.fileName }
@@ -546,6 +552,8 @@ abstract class BasicBoxTest(
             safeExternalBooleanDiagnostic,
             skipMangleVerification,
             abiVersion,
+            checkIC,
+            recompile = false,
             icCache
         )
 
@@ -568,12 +576,13 @@ abstract class BasicBoxTest(
                 testPackage,
                 testFunction,
                 needsFullIrRuntime,
-                expectActualLinker
+                expectActualLinker,
+                icCache
             )
         }
     }
 
-    private fun checkIncrementalCompilation(
+    protected open fun checkIncrementalCompilation(
         sourceDirs: List<String>,
         module: TestModule,
         kotlinFiles: List<TestFile>,
@@ -591,7 +600,8 @@ abstract class BasicBoxTest(
         testPackage: String?,
         testFunction: String,
         needsFullIrRuntime: Boolean,
-        expectActualLinker: Boolean
+        expectActualLinker: Boolean,
+        icCaches: MutableMap<String, ICCache>
     ) {
         val sourceToTranslationUnit = hashMapOf<File, TranslationUnit>()
         for (testFile in kotlinFiles) {
@@ -645,6 +655,8 @@ abstract class BasicBoxTest(
             safeExternalBooleanDiagnostic = null,
             skipMangleVerification = false,
             abiVersion = KotlinAbiVersion.CURRENT,
+            incrementalCompilation = true,
+            recompile = true,
             mutableMapOf()
         )
 
@@ -729,7 +741,9 @@ abstract class BasicBoxTest(
         safeExternalBooleanDiagnostic: RuntimeDiagnostic?,
         skipMangleVerification: Boolean,
         abiVersion: KotlinAbiVersion,
-        icCache: MutableMap<String, SerializedIcData>
+        incrementalCompilation: Boolean,
+        recompile: Boolean,
+        icCache: MutableMap<String, ICCache>
     ) {
         val translator = K2JSTranslator(config, false)
         val translationResult = translator.translateUnits(ExceptionThrowingReporter, units, mainCallParameters)
@@ -866,7 +880,7 @@ abstract class BasicBoxTest(
 
     private fun createPsiFiles(fileNames: List<String>): List<KtFile> = fileNames.map(this::createPsiFile)
 
-    private fun createConfig(
+    protected fun createConfig(
         sourceDirs: List<String>,
         module: TestModule,
         dependencies: List<String>,
@@ -1069,13 +1083,13 @@ abstract class BasicBoxTest(
         }
     }
 
-    private class TestFile(val fileName: String, val module: TestModule, val recompile: Boolean, val packageName: String) {
+    protected class TestFile(val fileName: String, val module: TestModule, val recompile: Boolean, val packageName: String) {
         init {
             module.files += this
         }
     }
 
-    private class TestModule(
+    protected class TestModule(
         name: String,
         dependencies: List<String>,
         friends: List<String>,
@@ -1147,7 +1161,7 @@ abstract class BasicBoxTest(
         protected val runTestInNashorn = getBoolean("kotlin.js.useNashorn")
 
         const val TEST_MODULE = "JS_TESTS"
-        private const val DEFAULT_MODULE = "main"
+        const val DEFAULT_MODULE = "main"
         private const val TEST_FUNCTION = "box"
         private const val OLD_MODULE_SUFFIX = "-old"
 
diff --git a/js/js.tests/test/org/jetbrains/kotlin/js/test/BasicIrBoxTest.kt b/js/js.tests/test/org/jetbrains/kotlin/js/test/BasicIrBoxTest.kt
index 588c5e9fbd1..ec8b7cedf85 100644
--- a/js/js.tests/test/org/jetbrains/kotlin/js/test/BasicIrBoxTest.kt
+++ b/js/js.tests/test/org/jetbrains/kotlin/js/test/BasicIrBoxTest.kt
@@ -5,15 +5,16 @@
 
 package org.jetbrains.kotlin.js.test
 
+import com.intellij.openapi.util.io.FileUtil
 import org.jetbrains.kotlin.backend.common.phaser.AnyNamedPhase
 import org.jetbrains.kotlin.backend.common.phaser.PhaseConfig
 import org.jetbrains.kotlin.backend.common.phaser.toPhaseMap
 import org.jetbrains.kotlin.cli.common.messages.AnalyzerWithCompilerReport
 import org.jetbrains.kotlin.ir.backend.js.*
-import org.jetbrains.kotlin.ir.backend.js.ic.SerializedIcData
-import org.jetbrains.kotlin.ir.backend.js.ic.prepareSingleLibraryIcCache
+import org.jetbrains.kotlin.ir.backend.js.ic.*
 import org.jetbrains.kotlin.ir.declarations.impl.IrFactoryImpl
 import org.jetbrains.kotlin.ir.declarations.persistent.PersistentIrFactory
+import org.jetbrains.kotlin.js.config.ErrorTolerancePolicy
 import org.jetbrains.kotlin.js.config.JSConfigurationKeys
 import org.jetbrains.kotlin.js.config.JsConfig
 import org.jetbrains.kotlin.js.config.RuntimeDiagnostic
@@ -32,7 +33,7 @@ private val defaultRuntimeKlib = System.getProperty("kotlin.js.reduced.stdlib.pa
 private val kotlinTestKLib = System.getProperty("kotlin.js.kotlin.test.path")
 
 // TODO Cache on FS (requires bootstrap)
-private val predefinedKlibHasIcCache = mutableMapOf<String, SerializedIcData?>(
+private val predefinedKlibHasIcCache = mutableMapOf<String, ICCache?>(
     File(fullRuntimeKlib).absolutePath to null,
     File(kotlinTestKLib).absolutePath to null,
     File(defaultRuntimeKlib).absolutePath to null
@@ -75,7 +76,7 @@ abstract class BasicIrBoxTest(
     val perModule: Boolean = getBoolean("kotlin.js.ir.perModule")
 
     // TODO Design incremental compilation for IR and add test support
-    override val incrementalCompilationChecksEnabled = false
+    override val incrementalCompilationChecksEnabled = true
 
     private val compilationCache = mutableMapOf<String, String>()
 
@@ -111,9 +112,11 @@ abstract class BasicIrBoxTest(
         safeExternalBooleanDiagnostic: RuntimeDiagnostic?,
         skipMangleVerification: Boolean,
         abiVersion: KotlinAbiVersion,
-        icCache: MutableMap<String, SerializedIcData>
+        incrementalCompilation: Boolean,
+        recompile: Boolean,
+        icCache: MutableMap<String, ICCache>
     ) {
-        val filesToCompile = units.map { (it as TranslationUnit.SourceFile).file }
+        val filesToCompile = units.mapNotNull { (it as? TranslationUnit.SourceFile)?.file }
 
         val runtimeKlibs = if (needsFullIrRuntime) listOf(fullRuntimeKlib, kotlinTestKLib) else listOf(defaultRuntimeKlib)
 
@@ -123,11 +126,17 @@ abstract class BasicIrBoxTest(
             compilationCache[it] ?: error("Can't find compiled module for dependency $it")
         }).map { File(it).absolutePath }.toMutableList()
 
-        val klibPath = outputFile.absolutePath.replace("_v5.js", "")
+        val klibPath = outputFile.canonicalPath.replace("_v5.js", "")
 
-        prepareRuntimePirCaches(config, icCache)
+        val actualOutputFile = outputFile.canonicalPath.let {
+            if (!isMainModule) klibPath else it
+        }
 
-        if (isMainModule && klibMainModule) {
+        if (incrementalCompilationChecksEnabled && incrementalCompilation) {
+            runtimeKlibs.forEach { createIcCache(it, runtimeKlibs, config, icCache) }
+        }
+
+        if (!recompile) { // In case of incremental recompilation we only rebuild caches, not klib itself
             val module = prepareAnalyzedSourceModule(
                 config.project,
                 filesToCompile,
@@ -143,14 +152,16 @@ abstract class BasicIrBoxTest(
                 nopack = true,
                 jsOutputName = null
             )
-
-            allKlibPaths += File(klibPath).absolutePath
         }
 
-        val actualOutputFile = outputFile.absolutePath.let {
-            if (!isMainModule) klibPath else it
+        val klibCannonPath = File(klibPath).canonicalPath
+
+        if (incrementalCompilation) {
+            icCache[klibCannonPath] = createIcCache(klibCannonPath, allKlibPaths + klibCannonPath, config, icCache)
         }
 
+        compilationCache[outputFile.name.replace(".js", ".meta.js")] = actualOutputFile
+
         if (isMainModule) {
             logger.logFile("Output JS", outputFile)
 
@@ -171,47 +182,27 @@ abstract class BasicIrBoxTest(
                 PhaseConfig(jsPhases)
             }
 
-            fun prepareModule(allowIc: Boolean): ModulesStructure {
-                val useIc = runIcMode && allowIc
-                @Suppress("NAME_SHADOWING")
-                val icCache = if (useIc) icCache else emptyMap()
-                return if (!klibMainModule) {
-                    prepareAnalyzedSourceModule(
-                        config.project,
-                        filesToCompile,
-                        config.configuration,
-                        allKlibPaths,
-                        emptyList(),
-                        AnalyzerWithCompilerReport(config.configuration),
-                        icUseGlobalSignatures = useIc,
-                        icUseStdlibCache = useIc,
-                        icCache = icCache
-                    )
-                } else {
-                    ModulesStructure(
-                        config.project,
-                        MainModule.Klib(klibPath),
-                        config.configuration,
-                        allKlibPaths,
-                        emptyList(),
-                        icUseGlobalSignatures = useIc,
-                        icUseStdlibCache = useIc,
-                        icCache = icCache
-                    )
-                }
-            }
+            val module = ModulesStructure(
+                config.project,
+                MainModule.Klib(klibPath),
+                config.configuration,
+                allKlibPaths + klibCannonPath,
+                emptyList(),
+                icUseGlobalSignatures = runIcMode,
+                icUseStdlibCache = runIcMode,
+                icCache = icCache
+            )
 
             if (!skipRegularMode) {
-                val module = prepareModule(true)
-                val irFactory = if (lowerPerModule) PersistentIrFactory() else IrFactoryImpl
                 val compiledModule = compile(
                     module,
                     phaseConfig = phaseConfig,
-                    irFactory = irFactory,
+                    irFactory = IrFactoryImpl,
                     mainArguments = mainCallParameters.run { if (shouldBeGenerated()) arguments() else null },
                     exportedDeclarations = setOf(FqName.fromSegments(listOfNotNull(testPackage, testFunction))),
                     generateFullJs = true,
                     generateDceJs = runIrDce,
+                    dceDriven = false,
                     es6mode = runEs6Mode,
                     multiModule = splitPerModule || perModule,
                     propertyLazyInitialization = propertyLazyInitialization,
@@ -221,7 +212,10 @@ abstract class BasicIrBoxTest(
                     verifySignatures = !skipMangleVerification,
                 )
 
-                compiledModule.outputs!!.writeTo(outputFile, config)
+                val jsOutputFile = if (recompile) File(outputFile.parentFile, outputFile.nameWithoutExtension + "-recompiled.js")
+                else outputFile
+
+                compiledModule.outputs!!.writeTo(jsOutputFile, config)
 
                 compiledModule.outputsAfterDce?.writeTo(dceOutputFile, config)
 
@@ -232,54 +226,127 @@ abstract class BasicIrBoxTest(
                 }
             }
 
-            if (runIrPir && !skipDceDriven) {
-                val module = prepareModule(false)
-                compile(
+            if (runIrPir) {
+                val compiledModule = compile(
                     module,
                     phaseConfig = phaseConfig,
                     irFactory = PersistentIrFactory(),
                     mainArguments = mainCallParameters.run { if (shouldBeGenerated()) arguments() else null },
                     exportedDeclarations = setOf(FqName.fromSegments(listOfNotNull(testPackage, testFunction))),
+                    generateFullJs = true,
+                    generateDceJs = runIrDce,
                     dceDriven = true,
                     es6mode = runEs6Mode,
                     multiModule = splitPerModule || perModule,
                     propertyLazyInitialization = propertyLazyInitialization,
+                    lowerPerModule = lowerPerModule,
                     safeExternalBoolean = safeExternalBoolean,
                     safeExternalBooleanDiagnostic = safeExternalBooleanDiagnostic,
-                    verifySignatures = !skipMangleVerification
-                ).outputs!!.writeTo(pirOutputFile, config)
+                    verifySignatures = !skipMangleVerification,
+                )
+                compiledModule.outputs!!.writeTo(pirOutputFile, config)
             }
-        } else {
-            val module = prepareAnalyzedSourceModule(
-                config.project,
-                filesToCompile,
-                config.configuration,
-                allKlibPaths,
-                emptyList(),
-                AnalyzerWithCompilerReport(config.configuration)
-            )
-            generateKLib(
-                module,
-                irFactory = IrFactoryImpl,
-                outputKlibPath = actualOutputFile,
-                nopack = true,
-                verifySignatures = !skipMangleVerification,
-                abiVersion = abiVersion,
-                null
-            )
-
-            if (runIcMode) {
-                icCache[actualOutputFile] = createPirCache(actualOutputFile, allKlibPaths + actualOutputFile, config, icCache)
-            }
-
-            logger.logFile("Output klib", File(actualOutputFile))
-
-            compilationCache[outputFile.name.replace(".js", ".meta.js")] = actualOutputFile
         }
     }
 
+    override fun checkIncrementalCompilation(
+        sourceDirs: List<String>,
+        module: TestModule,
+        kotlinFiles: List<TestFile>,
+        dependencies: List<String>,
+        allDependencies: List<String>,
+        friends: List<String>,
+        multiModule: Boolean,
+        tmpDir: File,
+        remap: Boolean,
+        outputFile: File,
+        outputPrefixFile: File?,
+        outputPostfixFile: File?,
+        mainCallParameters: MainCallParameters,
+        incrementalData: IncrementalData,
+        testPackage: String?,
+        testFunction: String,
+        needsFullIrRuntime: Boolean,
+        expectActualLinker: Boolean,
+        icCaches: MutableMap<String, ICCache>
+    ) {
+        val isMainModule = module.name == DEFAULT_MODULE || module.name == TEST_MODULE
+        val cacheKey = outputFile.canonicalPath.replace("_v5.js", "")
 
-    private fun createPirCache(path: String, allKlibPaths: Collection<String>, config: JsConfig, icCache: Map<String, SerializedIcData>): SerializedIcData {
+        val icCache = icCaches[cacheKey] ?: error("No IC data found for module ${module.name}")
+
+        val dirtyFiles = mutableListOf<String>()
+        val oldBinaryAsts = mutableMapOf<String, ByteArray>()
+
+        for (testFile in kotlinFiles) {
+            if (testFile.recompile) {
+                val fileName = testFile.fileName
+                oldBinaryAsts[fileName] = icCache.dataProvider.binaryAst(fileName)
+                icCache.dataConsumer.invalidateForFile(fileName)
+                dirtyFiles.add(fileName)
+            }
+        }
+
+        val recompiledOutputFile = File(outputFile.parentFile, outputFile.nameWithoutExtension + "-recompiled.js")
+        val recompiledMinOutputFile = File(recompiledOutputFile.parentFile, recompiledOutputFile.nameWithoutExtension + "-min.js")
+        val recompiledPirOutputFile = File(recompiledOutputFile.parentFile, recompiledOutputFile.nameWithoutExtension + "-pir.js")
+        val recompiledConfig = createConfig(
+            sourceDirs,
+            module,
+            dependencies,
+            allDependencies,
+            friends,
+            multiModule,
+            tmpDir,
+            null,
+            expectActualLinker,
+            ErrorTolerancePolicy.DEFAULT
+        )
+
+        translateFiles(
+            dirtyFiles.map { TranslationUnit.SourceFile(createPsiFile(it)) },
+            outputFile,
+            recompiledMinOutputFile,
+            recompiledPirOutputFile,
+            recompiledConfig,
+            outputPrefixFile,
+            outputPostfixFile,
+            mainCallParameters,
+            incrementalData,
+            remap,
+            testPackage,
+            testFunction,
+            needsFullIrRuntime,
+            isMainModule,
+            skipDceDriven = true,
+            splitPerModule = false, // TODO??
+            propertyLazyInitialization = false, // ??
+            safeExternalBoolean = false,
+            safeExternalBooleanDiagnostic = null,
+            skipMangleVerification = false,
+            KotlinAbiVersion.CURRENT,
+            incrementalCompilation = true,
+            recompile = true,
+            icCaches
+        )
+
+        val newBinaryAsts = dirtyFiles.associateWith { icCache.dataProvider.binaryAst(it) }
+
+        for (file in dirtyFiles) {
+            val oldBinaryAst = oldBinaryAsts[file]
+            val newBinaryAst = newBinaryAsts[file]
+
+            assert(oldBinaryAst.contentEquals(newBinaryAst)) { "Binary AST changed after recompilation for file $file" }
+        }
+
+        if (isMainModule) {
+            val originalOutput = FileUtil.loadFile(outputFile)
+            val recompiledOutput = FileUtil.loadFile(recompiledOutputFile)
+            assertEquals("Output file changed after recompilation", originalOutput, recompiledOutput)
+        }
+    }
+
+    private fun createPirCache(path: String, allKlibPaths: Collection<String>, config: JsConfig, icCache: Map<String, ICCache>): ICCache {
         val icData = predefinedKlibHasIcCache[path] ?: prepareSingleLibraryIcCache(
             project = project,
             configuration = config.configuration,
@@ -295,7 +362,23 @@ abstract class BasicIrBoxTest(
         return icData
     }
 
-    private fun prepareRuntimePirCaches(config: JsConfig, icCache: MutableMap<String, SerializedIcData>) {
+    @Suppress("UNUSED_PARAMETER")
+    private fun createIcCache(path: String, allKlibPaths: Collection<String>, config: JsConfig, icCache: Map<String, ICCache>): ICCache {
+
+        fun prepare(): ICCache {
+            return ICCache(PersistentCacheProvider.EMPTY, PersistentCacheConsumer.EMPTY, SerializedIcData(emptyList()))
+        }
+
+        val icData = predefinedKlibHasIcCache[path] ?: prepare()
+
+        if (path in predefinedKlibHasIcCache) {
+            predefinedKlibHasIcCache[path] = icData
+        }
+
+        return icData
+    }
+
+    private fun prepareRuntimePirCaches(config: JsConfig, icCache: MutableMap<String, ICCache>) {
         if (!runIcMode) return
 
         val defaultRuntimePath = File(defaultRuntimeKlib).canonicalPath