diff --git a/compiler/frontend/src/org/jetbrains/kotlin/script/KotlinScriptDefinition.kt b/compiler/frontend/src/org/jetbrains/kotlin/script/KotlinScriptDefinition.kt
index e2b6da55f9b..708e0f129db 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/script/KotlinScriptDefinition.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/script/KotlinScriptDefinition.kt
@@ -23,6 +23,7 @@ import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.parsing.KotlinParserDefinition
 import org.jetbrains.kotlin.psi.KtScript
 import java.io.File
+import kotlin.comparisons.compareValues
 import kotlin.reflect.KClass
 import kotlin.script.templates.standard.ScriptTemplateWithArgs
 
@@ -42,13 +43,33 @@ open class KotlinScriptDefinition(val template: KClass<out Any>) {
     open fun <TF> getDependenciesFor(file: TF, project: Project, previousDependencies: KotlinScriptExternalDependencies?): KotlinScriptExternalDependencies? = null
 }
 
-interface KotlinScriptExternalDependencies {
+interface KotlinScriptExternalDependencies : Comparable<KotlinScriptExternalDependencies> {
     val javaHome: String? get() = null
     val classpath: Iterable<File> get() = emptyList()
     val imports: Iterable<String> get() = emptyList()
     val sources: Iterable<File> get() = emptyList()
     val scripts: Iterable<File> get() = emptyList()
+
+    override fun compareTo(other: KotlinScriptExternalDependencies): Int =
+            compareValues(javaHome, other.javaHome)
+            .chainCompare { compareIterables(classpath, other.classpath) }
+            .chainCompare { compareIterables(imports, other.imports) }
+            .chainCompare { compareIterables(sources, other.sources) }
+            .chainCompare { compareIterables(scripts, other.scripts) }
 }
 
 object StandardScriptDefinition : KotlinScriptDefinition(ScriptTemplateWithArgs::class)
 
+private fun<T: Comparable<T>> compareIterables(a: Iterable<T>, b: Iterable<T>): Int {
+    val ia = a.iterator()
+    val ib = b.iterator()
+    while (true) {
+        if (ia.hasNext() && !ib.hasNext()) return 1
+        if (!ia.hasNext() && !ib.hasNext()) return 0
+        if (!ia.hasNext()) return -1
+        val compRes = compareValues(ia.next(), ib.next())
+        if (compRes != 0) return compRes
+    }
+}
+
+private inline fun Int.chainCompare(compFn: () -> Int ): Int = if (this != 0) this else compFn()
\ No newline at end of file
diff --git a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/KotlinCacheServiceImpl.kt b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/KotlinCacheServiceImpl.kt
index 9367dc6339c..65673e90ecf 100644
--- a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/KotlinCacheServiceImpl.kt
+++ b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/KotlinCacheServiceImpl.kt
@@ -39,6 +39,7 @@ import org.jetbrains.kotlin.container.getService
 import org.jetbrains.kotlin.context.GlobalContext
 import org.jetbrains.kotlin.context.GlobalContextImpl
 import org.jetbrains.kotlin.descriptors.annotations.AnnotationDescriptor
+import org.jetbrains.kotlin.idea.core.script.ScriptDependenciesModificationTracker
 import org.jetbrains.kotlin.idea.project.AnalyzerFacadeProvider
 import org.jetbrains.kotlin.idea.project.TargetPlatformDetector
 import org.jetbrains.kotlin.idea.project.outOfBlockModificationCount
@@ -52,6 +53,7 @@ import org.jetbrains.kotlin.resolve.TargetPlatform
 import org.jetbrains.kotlin.resolve.diagnostics.KotlinSuppressCache
 import org.jetbrains.kotlin.resolve.jvm.platform.JvmPlatform
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
+import org.jetbrains.kotlin.script.KotlinScriptExternalDependencies
 import org.jetbrains.kotlin.utils.addToStdlib.firstIsInstanceOrNull
 import org.jetbrains.kotlin.utils.addToStdlib.sumByLong
 import java.lang.AssertionError
@@ -74,14 +76,14 @@ class KotlinCacheServiceImpl(val project: Project) : KotlinCacheService {
             }
 
 
-    private val facadesForScriptDependencies: SLRUCache<ComparableScriptDependencies, ProjectResolutionFacade> =
-            object : SLRUCache<ComparableScriptDependencies, ProjectResolutionFacade>(2, 3) {
-                override fun createValue(key: ComparableScriptDependencies?): ProjectResolutionFacade {
+    private val facadesForScriptDependencies: SLRUCache<KotlinScriptExternalDependencies, ProjectResolutionFacade> =
+            object : SLRUCache<KotlinScriptExternalDependencies, ProjectResolutionFacade>(2, 3) {
+                override fun createValue(key: KotlinScriptExternalDependencies?): ProjectResolutionFacade {
                     return createFacadeForScriptDependencies(ScriptDependenciesModuleInfo(project, key))
                 }
             }
 
-    private fun getFacadeForScriptDependencies(dependencies: ComparableScriptDependencies?) = synchronized(facadesForScriptDependencies) {
+    private fun getFacadeForScriptDependencies(dependencies: KotlinScriptExternalDependencies?) = synchronized(facadesForScriptDependencies) {
         facadesForScriptDependencies.get(dependencies)
     }
 
@@ -105,7 +107,8 @@ class KotlinCacheServiceImpl(val project: Project) : KotlinCacheService {
                         //TODO: provide correct trackers
                         dependencies = listOf(
                                 LibraryModificationTracker.getInstance(project),
-                                ProjectRootModificationTracker.getInstance(project)
+                                ProjectRootModificationTracker.getInstance(project),
+                                ScriptDependenciesModificationTracker.getInstance(project)
                         ),
                         moduleFilter = { it == dependenciesModuleInfo },
                         syntheticFiles = syntheticFiles
diff --git a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ScriptModuleInfos.kt b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ScriptModuleInfos.kt
index b4aae4f1957..f31c503d0c2 100644
--- a/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ScriptModuleInfos.kt
+++ b/idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/ScriptModuleInfos.kt
@@ -17,7 +17,6 @@
 package org.jetbrains.kotlin.idea.caches.resolve
 
 import com.intellij.openapi.project.Project
-import com.intellij.openapi.projectRoots.ProjectJdkTable
 import com.intellij.openapi.projectRoots.Sdk
 import com.intellij.openapi.roots.ProjectRootManager
 import com.intellij.openapi.vfs.VirtualFile
@@ -31,7 +30,6 @@ import org.jetbrains.kotlin.script.KotlinScriptDefinition
 import org.jetbrains.kotlin.script.KotlinScriptExternalDependencies
 import org.jetbrains.kotlin.script.KotlinScriptExternalImportsProvider
 import org.jetbrains.kotlin.utils.singletonOrEmptyList
-import java.io.File
 
 private val SCRIPT_NAME_PREFIX: String = "script "
 
@@ -47,7 +45,7 @@ data class ScriptModuleInfo(val project: Project, val scriptFile: VirtualFile,
         get() = ModuleOrigin.OTHER
 
     val externalDependencies by lazy {
-        KotlinScriptExternalImportsProvider.getInstance(project)?.getExternalImports(scriptFile)?.makeComparable()
+        KotlinScriptExternalImportsProvider.getInstance(project)?.getExternalImports(scriptFile)
     }
 
     override val name: Name = Name.special("<$SCRIPT_NAME_PREFIX${scriptDefinition.name}>")
@@ -75,29 +73,8 @@ fun findJdk(dependencies: KotlinScriptExternalDependencies?, project: Project):
            allJdks.firstOrNull()
 }
 
-private inline fun <T> tryGet(body: () -> T): T? {
-    return try {
-        body()
-    }
-    catch (e: Throwable) {
-        null
-    }
-}
-
-data class ComparableScriptDependencies(
-        override val javaHome: String?,
-        override val classpath: Iterable<File>,
-        override val imports: Iterable<String>,
-        override val sources: Iterable<File>,
-        override val scripts: Iterable<File>
-): KotlinScriptExternalDependencies
-
-fun KotlinScriptExternalDependencies.makeComparable() = ComparableScriptDependencies(
-        tryGet { javaHome }, classpath, imports, sources, tryGet { scripts } ?: listOf()
-)
-
-class ScriptDependenciesModuleInfo(val project: Project, val dependencies: ComparableScriptDependencies?): IdeaModuleInfo {
-    override fun dependencies() = listOf(this) + sdkDependencies(dependencies, project)
+class ScriptDependenciesModuleInfo(val project: Project, val dependencies: KotlinScriptExternalDependencies?): IdeaModuleInfo {
+    override fun dependencies() = (listOf(this) + sdkDependencies(dependencies, project))
 
     override val name = Name.special("<Script dependencies>")
 
diff --git a/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptConfigurationManager.kt b/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptConfigurationManager.kt
index 980129663a2..9912484e13f 100644
--- a/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptConfigurationManager.kt
+++ b/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptConfigurationManager.kt
@@ -19,6 +19,7 @@ package org.jetbrains.kotlin.idea.core.script
 import com.intellij.openapi.application.ApplicationManager
 import com.intellij.openapi.components.ServiceManager
 import com.intellij.openapi.diagnostic.Logger
+import com.intellij.openapi.project.DumbService
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.roots.ex.ProjectRootManagerEx
 import com.intellij.openapi.startup.StartupManager
@@ -47,6 +48,7 @@ import kotlin.concurrent.write
 @Suppress("SimplifyAssertNotNull")
 class KotlinScriptConfigurationManager(
         private val project: Project,
+        private val dumbService: DumbService,
         private val scriptDefinitionProvider: KotlinScriptDefinitionProvider,
         private val scriptExternalImportsProvider: KotlinScriptExternalImportsProvider
 ) {
@@ -76,14 +78,27 @@ class KotlinScriptConfigurationManager(
         toVfsRoots(scriptExternalImportsProvider.getKnownCombinedClasspath().distinct())
     }
 
+    private val allScriptsClasspathScope = ClearableLazyValue(cacheLock) {
+        NonClasspathDirectoriesScope(getAllScriptsClasspath())
+    }
+
     private val allLibrarySourcesCache = ClearableLazyValue(cacheLock) {
         toVfsRoots(scriptExternalImportsProvider.getKnownSourceRoots().distinct())
     }
 
+    private val allLibrarySourcesScope = ClearableLazyValue(cacheLock) {
+        NonClasspathDirectoriesScope(getAllLibrarySources())
+    }
+
     private fun notifyRootsChanged() {
         // TODO: it seems invokeLater leads to inconsistent behaviour (at least in tests)
         ApplicationManager.getApplication().invokeLater {
-            runWriteAction { ProjectRootManagerEx.getInstanceEx(project)?.makeRootsChange(EmptyRunnable.getInstance(), false, true) }
+            runWriteAction {
+                ProjectRootManagerEx.getInstanceEx(project)?.makeRootsChange(EmptyRunnable.getInstance(), false, true)
+                dumbService.runWhenSmart {
+                    ScriptDependenciesModificationTracker.getInstance(project).incModificationCount()
+                }
+            }
         }
     }
 
@@ -95,9 +110,9 @@ class KotlinScriptConfigurationManager(
 
     fun getAllLibrarySources(): List<VirtualFile> = allLibrarySourcesCache.get()
 
-    fun getAllScriptsClasspathScope() = NonClasspathDirectoriesScope(getAllScriptsClasspath())
+    fun getAllScriptsClasspathScope() = allScriptsClasspathScope.get()
 
-    fun getAllLibrarySourcesScope() = NonClasspathDirectoriesScope(getAllLibrarySources())
+    fun getAllLibrarySourcesScope() = allLibrarySourcesScope.get()
 
     private fun reloadScriptDefinitions() {
         makeScriptDefsFromTemplatesProviderExtensions(project, { ep, ex -> log.warn("[kts] Error loading definition from ${ep.id}", ex) }).let {
@@ -127,7 +142,9 @@ class KotlinScriptConfigurationManager(
 
     private fun invalidateLocalCaches() {
         allScriptsClasspathCache.clear()
+        allScriptsClasspathScope.clear()
         allLibrarySourcesCache.clear()
+        allLibrarySourcesScope.clear()
     }
 
 
diff --git a/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptDependenciesClassFinder.kt b/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptDependenciesClassFinder.kt
index 76c70c24de9..ab09aa1a476 100644
--- a/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptDependenciesClassFinder.kt
+++ b/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptDependenciesClassFinder.kt
@@ -26,7 +26,6 @@ import com.intellij.psi.search.EverythingGlobalScope
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.util.containers.ConcurrentFactoryMap
 import org.jetbrains.kotlin.idea.caches.resolve.ScriptModuleSearchScope
-import org.jetbrains.kotlin.idea.core.script.KotlinScriptConfigurationManager
 import org.jetbrains.kotlin.load.java.JavaClassFinderImpl
 import org.jetbrains.kotlin.resolve.jvm.KotlinSafeClassFinder
 
@@ -34,22 +33,23 @@ class KotlinScriptDependenciesClassFinder(project: Project,
                                           private val kotlinScriptConfigurationManager: KotlinScriptConfigurationManager
 ) : NonClasspathClassFinder(project), KotlinSafeClassFinder {
 
-    private val myCaches = object : ConcurrentFactoryMap<VirtualFile, PackageDirectoryCache>() {
-        override fun create(file: VirtualFile): PackageDirectoryCache? {
-
-            val scriptClasspath = kotlinScriptConfigurationManager.getScriptClasspath(file)
-            val v = createCache(scriptClasspath)
-            return v
+    private val myCaches by lazy {
+        object : ConcurrentFactoryMap<VirtualFile, PackageDirectoryCache>() {
+            override fun create(file: VirtualFile): PackageDirectoryCache? {
+                val scriptClasspath = kotlinScriptConfigurationManager.getScriptClasspath(file)
+                val v = createCache(scriptClasspath)
+                return v
+            }
         }
     }
 
-    override fun calcClassRoots(): List<VirtualFile> = kotlinScriptConfigurationManager.getAllScriptsClasspath()
+    override fun calcClassRoots(): List<VirtualFile> = kotlinScriptConfigurationManager.getAllScriptsClasspath().toList()
 
     override fun getCache(scope: GlobalSearchScope?): PackageDirectoryCache =
             (scope as? ScriptModuleSearchScope ?:
              (scope as? JavaClassFinderImpl.FilterOutKotlinSourceFilesScope)?.base as? ScriptModuleSearchScope
             )?.let {
-                myCaches.get(it.scriptFile)
+                myCaches[it.scriptFile]
             } ?: super.getCache(scope)
 
     override fun clearCache() {
diff --git a/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/ScriptDependenciesModificationTracker.kt b/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/ScriptDependenciesModificationTracker.kt
new file mode 100644
index 00000000000..64836025e01
--- /dev/null
+++ b/idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/ScriptDependenciesModificationTracker.kt
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2010-2016 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.idea.core.script
+
+import com.intellij.openapi.components.ServiceManager
+import com.intellij.openapi.project.Project
+import com.intellij.openapi.util.SimpleModificationTracker
+
+class ScriptDependenciesModificationTracker(): SimpleModificationTracker() {
+
+    companion object {
+        @JvmStatic
+        fun getInstance(project: Project): ScriptDependenciesModificationTracker =
+                ServiceManager.getService(project, ScriptDependenciesModificationTracker::class.java)!!
+    }
+}
\ No newline at end of file
diff --git a/idea/src/META-INF/plugin.xml b/idea/src/META-INF/plugin.xml
index b00ec74e7ec..8ea34abcb53 100644
--- a/idea/src/META-INF/plugin.xml
+++ b/idea/src/META-INF/plugin.xml
@@ -282,6 +282,9 @@
     <projectService serviceInterface="org.jetbrains.kotlin.idea.caches.resolve.LibraryModificationTracker"
                     serviceImplementation="org.jetbrains.kotlin.idea.caches.resolve.LibraryModificationTracker"/>
 
+    <projectService serviceInterface="org.jetbrains.kotlin.idea.core.script.ScriptDependenciesModificationTracker"
+                    serviceImplementation="org.jetbrains.kotlin.idea.core.script.ScriptDependenciesModificationTracker"/>
+
     <projectService serviceInterface="org.jetbrains.kotlin.resolve.jvm.KotlinJavaPsiFacade"
                     serviceImplementation="org.jetbrains.kotlin.resolve.jvm.KotlinJavaPsiFacade"/>