diff --git a/libraries/tools/kotlin-gradle-plugin-idea/src/test/kotlin/org/jetbrains/kotlin/gradle/kpm/idea/testUtils/CompatibilityTestUtil.kt b/libraries/tools/kotlin-gradle-plugin-idea/src/test/kotlin/org/jetbrains/kotlin/gradle/kpm/idea/testUtils/CompatibilityTestUtil.kt
new file mode 100644
index 00000000000..69c5db6b7ca
--- /dev/null
+++ b/libraries/tools/kotlin-gradle-plugin-idea/src/test/kotlin/org/jetbrains/kotlin/gradle/kpm/idea/testUtils/CompatibilityTestUtil.kt
@@ -0,0 +1,62 @@
+/*
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.gradle.kpm.idea.testUtils
+
+import org.jetbrains.kotlin.gradle.kpm.idea.IdeaKpmProject
+import org.jetbrains.kotlin.gradle.kpm.idea.serialize.IdeaKpmSerializationLogger
+import org.jetbrains.kotlin.gradle.kpm.idea.testFixtures.TestIdeaKpmClassLoaderProjectSerializer
+import java.io.File
+import java.net.URLClassLoader
+import kotlin.test.assertEquals
+import kotlin.test.assertNotNull
+import kotlin.test.assertSame
+
+/*
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+fun classLoaderForBackwardsCompatibleClasses(): ClassLoader {
+    val uris = classpathForBackwardsCompatibleClasses().map { file -> file.toURI().toURL() }.toTypedArray()
+    return URLClassLoader.newInstance(uris, null)
+}
+
+fun classpathForBackwardsCompatibleClasses(): List<File> {
+    val compatibilityTestClasspath = System.getProperty("compatibilityTestClasspath")
+        ?: error("Missing compatibilityTestClasspath system property")
+
+    return compatibilityTestClasspath.split(";").map { path -> File(path) }
+        .onEach { file -> if (!file.exists()) println("[WARNING] Missing $file") }
+        .flatMap { file -> if (file.isDirectory) file.listFiles().orEmpty().toList() else listOf(file) }
+}
+
+fun deserializeIdeaKpmProjectWithBackwardsCompatibleClasses(project: IdeaKpmProject): Any {
+    return deserializeIdeaKpmProjectWithBackwardsCompatibleClasses(
+        TestIdeaKpmClassLoaderProjectSerializer().serialize(project)
+    )
+}
+
+fun deserializeIdeaKpmProjectWithBackwardsCompatibleClasses(project: ByteArray): Any {
+    val classLoader = classLoaderForBackwardsCompatibleClasses()
+    val serializer = TestIdeaKpmClassLoaderProjectSerializer(classLoader)
+
+    val deserialized = assertNotNull(
+        serializer.deserialize(project),
+        "Failed to deserialize project: ${serializer.reports}"
+    )
+
+    assertEquals(
+        0, serializer.reports.count { it.severity > IdeaKpmSerializationLogger.Severity.WARNING },
+        "Expected no severe deserialization reports. Found ${serializer.reports}"
+    )
+
+    assertSame(
+        classLoader, deserialized::class.java.classLoader,
+        "Expected model do be deserialized in with old classes"
+    )
+
+    return deserialized
+}
diff --git a/libraries/tools/kotlin-gradle-plugin-idea/src/test/kotlin/GradleUtils.kt b/libraries/tools/kotlin-gradle-plugin-idea/src/test/kotlin/org/jetbrains/kotlin/gradle/kpm/idea/testUtils/gradleUtils.kt
similarity index 66%
rename from libraries/tools/kotlin-gradle-plugin-idea/src/test/kotlin/GradleUtils.kt
rename to libraries/tools/kotlin-gradle-plugin-idea/src/test/kotlin/org/jetbrains/kotlin/gradle/kpm/idea/testUtils/gradleUtils.kt
index c6560edc262..65b32ff4af9 100644
--- a/libraries/tools/kotlin-gradle-plugin-idea/src/test/kotlin/GradleUtils.kt
+++ b/libraries/tools/kotlin-gradle-plugin-idea/src/test/kotlin/org/jetbrains/kotlin/gradle/kpm/idea/testUtils/gradleUtils.kt
@@ -1,3 +1,10 @@
+/*
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.gradle.kpm.idea.testUtils
+
 import org.gradle.api.Project
 import org.gradle.api.artifacts.verification.DependencyVerificationMode
 import org.gradle.api.internal.project.ProjectInternal
@@ -5,6 +12,8 @@ import org.gradle.configurationcache.extensions.serviceOf
 import org.gradle.testfixtures.ProjectBuilder
 import org.gradle.tooling.provider.model.ToolingModelBuilderRegistry
 import org.jetbrains.kotlin.gradle.kpm.idea.IdeaKpmProject
+import org.jetbrains.kotlin.gradle.kpm.idea.IdeaKpmProjectBinaryContainer
+import org.jetbrains.kotlin.gradle.kpm.idea.IdeaKpmProjectContainer
 import org.jetbrains.kotlin.gradle.plugin.KotlinPm20PluginWrapper
 import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.KotlinPm20ProjectExtension
 
@@ -13,11 +22,16 @@ import org.jetbrains.kotlin.gradle.plugin.mpp.pm20.KotlinPm20ProjectExtension
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
-fun Project.buildIdeaKpmProjectModel(): IdeaKpmProject {
+fun Project.buildIdeaKpmProject(): IdeaKpmProject {
     return serviceOf<ToolingModelBuilderRegistry>().getBuilder(IdeaKpmProject::class.java.name)
         .buildAll(IdeaKpmProject::class.java.name, this) as IdeaKpmProject
 }
 
+fun Project.buildIdeaKpmProjectBinary(): IdeaKpmProjectBinaryContainer {
+    return serviceOf<ToolingModelBuilderRegistry>().getBuilder(IdeaKpmProjectContainer::class.java.name)
+        .buildAll(IdeaKpmProjectContainer::class.java.name, this) as IdeaKpmProjectBinaryContainer
+}
+
 fun createKpmProject(): Pair<ProjectInternal, KotlinPm20ProjectExtension> {
     val project = ProjectBuilder.builder().build() as ProjectInternal
     project.plugins.apply(KotlinPm20PluginWrapper::class.java)