diff --git a/gradle-plugin/src/main/java/tracex/JarsIdentity.kt b/gradle-plugin/src/main/java/tracex/JarsIdentity.kt
new file mode 100644
index 0000000..744670e
--- /dev/null
+++ b/gradle-plugin/src/main/java/tracex/JarsIdentity.kt
@@ -0,0 +1,41 @@
+package tracex
+
+import org.gradle.api.file.ConfigurableFileCollection
+import org.gradle.work.ChangeType
+import org.gradle.work.InputChanges
+import java.io.File
+
+class JarsIdentity(
+  private val inputJars: ConfigurableFileCollection,
+  private val inputChanges: InputChanges,
+) {
+
+  fun compute(): JarChanges {
+    val (changed, addedOrRemoved) = inputChanges
+      .getFileChanges(inputJars)
+      .partition { it.changeType == ChangeType.MODIFIED }
+
+    val reprocessAll = !inputChanges.isIncremental || addedOrRemoved.isNotEmpty()
+    val changedFiles = changed.map { it.file }.toSet()
+    val hasChanged = { file: File -> reprocessAll || (file in changedFiles) }
+    val jarsInfo = inputJars.files.mapIndexedNotNull { index: Int, file: File ->
+      if (!hasChanged(file)) null
+      else FileInfo(
+        identity = index.toString(),
+        file = file,
+      )
+    }
+
+    return JarChanges(jarsInfo, reprocessAll)
+  }
+
+  data class JarChanges(
+    val jarsInfo: List<FileInfo>,
+    val reprocessAll: Boolean,
+  )
+
+  data class FileInfo(
+    val identity: String,
+    val file: File,
+  )
+}
\ No newline at end of file
diff --git a/gradle-plugin/src/main/java/tracex/TraceTransformTask.kt b/gradle-plugin/src/main/java/tracex/TraceTransformTask.kt
index 0a1c48c..809e5a9 100644
--- a/gradle-plugin/src/main/java/tracex/TraceTransformTask.kt
+++ b/gradle-plugin/src/main/java/tracex/TraceTransformTask.kt
@@ -20,6 +20,7 @@ import org.gradle.work.Incremental
 import org.gradle.work.InputChanges
 import org.gradle.workers.WorkAction
 import org.gradle.workers.WorkParameters
+import org.gradle.workers.WorkQueue
 import org.gradle.workers.WorkerExecutor
 import org.objectweb.asm.ClassReader
 import org.objectweb.asm.ClassWriter
@@ -27,7 +28,6 @@ import org.objectweb.asm.Opcodes
 import java.io.File
 import java.io.InputStream
 import java.io.OutputStream
-import java.security.MessageDigest
 import java.util.Locale
 import java.util.jar.JarEntry
 import java.util.jar.JarInputStream
@@ -71,50 +71,74 @@ abstract class TraceTransformTask : DefaultTask() {
     @TaskAction
     fun transform(inputChanges: InputChanges) {
         val workQueue = workerExecutor.noIsolation()
-
-        val changedJars = inputChanges.getFileChanges(allJarsFileCollection)
-        val changedClasses = inputChanges.getFileChanges(allDirectoriesFileCollection)
         val intermediate = intermediate.get().asFile
 
-        changedJars.forEach { changedJar ->
+        val intermediateJars = intermediate.resolve("jars")
+        val intermediateClasses = intermediate.resolve("classes")
+
+        transformJars(
+            inputChanges = inputChanges,
+            intermediate = intermediateJars,
+            workQueue = workQueue
+        )
+
+        transformClasses(
+            inputChanges = inputChanges,
+            intermediate = intermediateClasses,
+            workQueue = workQueue
+        )
+
+        workQueue.await()
+
+        mergeClasses(
+            outputJar.get().asFile,
+            intermediateClasses,
+            *(intermediateJars.listFiles() ?: emptyArray())
+        )
+    }
+
+    private fun transformJars(inputChanges: InputChanges, intermediate: File, workQueue: WorkQueue) {
+        val (jarChanges, reprocessAll) = JarsIdentity(
+            inputJars = allJarsFileCollection,
+            inputChanges = inputChanges
+        ).compute()
+
+        if (reprocessAll) {
+            intermediate.deleteRecursively()
+        }
+
+        jarChanges.forEach { changedJar ->
             workQueue.submit(TransformJar::class.java) {
-                it.rootDir.set(project.rootDir)
+                it.identity.set(changedJar.identity)
                 it.source.set(changedJar.file)
-                it.normalizedPath.set(changedJar.normalizedPath)
-                it.changeType.set(changedJar.changeType)
+                it.changeType.set(ChangeType.MODIFIED)
                 it.intermediate.set(intermediate)
             }
         }
+    }
 
-        changedClasses.forEach { changedClass ->
+    private fun transformClasses(inputChanges: InputChanges, intermediate: File, workQueue: WorkQueue) {
+        val classChanges = inputChanges.getFileChanges(allDirectoriesFileCollection)
+        classChanges.forEach { changedClass ->
             workQueue.submit(TransformClass::class.java) {
-                it.rootDir.set(project.rootDir)
-                it.source.set(changedClass.file)
                 it.normalizedPath.set(changedClass.normalizedPath)
+                it.source.set(changedClass.file)
                 it.changeType.set(changedClass.changeType)
                 it.intermediate.set(intermediate)
             }
         }
-
-        workQueue.await()
-
-        mergeClasses(
-            intermediate,
-            outputJar.get().asFile,
-        )
     }
 
     private fun mergeClasses(
-        intermediate: File,
         outputJar: File,
+        vararg classpath: File,
     ) {
         JarOutputStream(
             outputJar.outputStream()
                 .buffered()
         ).use { jar ->
             jar.setLevel(Deflater.NO_COMPRESSION)
-
-            intermediate.listFiles()?.forEach { rootDir ->
+            classpath.forEach { rootDir ->
                 rootDir.allFiles { child ->
                     val name = child.toRelativeString(rootDir)
                     val entry = JarEntry(name)
@@ -126,17 +150,11 @@ abstract class TraceTransformTask : DefaultTask() {
         }
     }
 
-    abstract class Transform : WorkAction<Transform.Parameters> {
-
-        protected val rootDir: File
-            get() = parameters.rootDir.get().asFile
+    abstract class Transform<T : Transform.Parameters> : WorkAction<T> {
 
         protected val source: File
             get() = parameters.source.get().asFile
 
-        protected val normalizedPath: String
-            get() = parameters.normalizedPath.get()
-
         protected val changeType: ChangeType
             get() = parameters.changeType.get()
 
@@ -148,7 +166,7 @@ abstract class TraceTransformTask : DefaultTask() {
         protected abstract fun transform()
 
         final override fun execute() {
-            println("[$changeType] $source($normalizedPath) -> $destination")
+            println("[$changeType] $source -> $destination")
 
             when (changeType) {
                 ChangeType.ADDED -> {
@@ -199,18 +217,18 @@ abstract class TraceTransformTask : DefaultTask() {
         }
 
         interface Parameters : WorkParameters {
-            val rootDir: DirectoryProperty
             val source: RegularFileProperty
-            val normalizedPath: Property<String>
             val changeType: Property<ChangeType>
             val intermediate: DirectoryProperty
         }
     }
 
-    abstract class TransformJar : Transform() {
+    abstract class TransformJar : Transform<TransformJar.Parameters>() {
+        val identity: String
+            get() = parameters.identity.get()
 
         override val destination: File
-            get() = File(intermediate, source.identify())
+            get() = File(intermediate, identity)
 
         override fun transform() {
             JarInputStream(
@@ -234,28 +252,18 @@ abstract class TraceTransformTask : DefaultTask() {
             }
         }
 
-        private fun File.identify(): String {
-            var current: File? = this
-            while (current != null) {
-                if (rootDir == current) {
-                    return toRelativeString(rootDir).toSha256()
-                }
-                current = current.parentFile
-            }
-            return name.toSha256()
-        }
-
-        private fun String.toSha256(): String {
-            val md = MessageDigest.getInstance("SHA-256")
-            val bytes = md.digest(this.toByteArray())
-            return bytes.joinToString("") { "%02x".format(it) }
+        interface Parameters : Transform.Parameters {
+            val identity: Property<String>
         }
     }
 
-    abstract class TransformClass : Transform() {
+    abstract class TransformClass : Transform<TransformClass.Parameters>() {
+
+        protected val normalizedPath: String
+            get() = parameters.normalizedPath.get()
 
         override val destination: File
-            get() = File(intermediate.resolve("classes"), normalizedPath)
+            get() = File(intermediate, normalizedPath)
 
         override fun transform() {
             if (!includeFileInTransform(normalizedPath)) return
@@ -272,6 +280,10 @@ abstract class TraceTransformTask : DefaultTask() {
                         }
                 }
         }
+
+        interface Parameters : Transform.Parameters {
+            val normalizedPath: Property<String>
+        }
     }
 
     private fun File.allFiles(block: (File) -> Unit) {