diff --git a/platform/editor-ui-api/src/com/intellij/codeInsight/actions/ReaderModeMatcher.kt b/platform/editor-ui-api/src/com/intellij/codeInsight/actions/ReaderModeMatcher.kt
new file mode 100644
index 000000000000..9cfff8651e39
--- /dev/null
+++ b/platform/editor-ui-api/src/com/intellij/codeInsight/actions/ReaderModeMatcher.kt
@@ -0,0 +1,18 @@
+// Copyright 2000-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.codeInsight.actions
+
+import com.intellij.codeInsight.actions.ReaderModeProvider.ReaderMode
+import com.intellij.openapi.project.Project
+import com.intellij.openapi.vfs.VirtualFile
+
+/**
+ * Use it to override file <--> reader mode matching
+ */
+interface ReaderModeMatcher {
+  /**
+   * It's triggered on Reader Mode to check if file matches mode specified.
+   *
+   * @return null if unable to decide
+   */
+  fun matches(project: Project, file: VirtualFile, mode: ReaderMode): Boolean?
+}
\ No newline at end of file
diff --git a/platform/platform-api/src/com/intellij/codeInsight/actions/ReaderModeSettings.kt b/platform/platform-api/src/com/intellij/codeInsight/actions/ReaderModeSettings.kt
index e9d23e1c1b2b..5c665ba4a67e 100644
--- a/platform/platform-api/src/com/intellij/codeInsight/actions/ReaderModeSettings.kt
+++ b/platform/platform-api/src/com/intellij/codeInsight/actions/ReaderModeSettings.kt
@@ -14,6 +14,7 @@ import com.intellij.psi.PsiManager
 class ReaderModeSettings : PersistentStateComponentWithModificationTracker<ReaderModeSettings.State> {
   companion object {
     private var EP_READER_MODE_PROVIDER = ExtensionPointName<ReaderModeProvider>("com.intellij.readerModeProvider")
+    private var EP_READER_MODE_MATCHER = ExtensionPointName<ReaderModeMatcher>("com.intellij.readerModeMatcher")
 
     @JvmStatic
     fun instance(project: Project): ReaderModeSettings {
@@ -32,12 +33,19 @@ class ReaderModeSettings : PersistentStateComponentWithModificationTracker<Reade
 
     fun matchMode(project: Project?, file: VirtualFile?): Boolean {
       if (project == null || file == null) return false
+      return matchMode(project, file, instance(project).mode)
+    }
 
-      val inLibraries = FileIndexFacade.getInstance(project).isInLibraryClasses(file) || FileIndexFacade.getInstance(
-        project).isInLibrarySource(file)
+    private fun matchMode(project: Project, file: VirtualFile, mode: ReaderMode): Boolean {
+      for (m in EP_READER_MODE_MATCHER.iterable) {
+        val matched = m.matches(project, file, mode)
+        if (matched != null) return matched
+      }
+      val inLibraries = FileIndexFacade.getInstance(project).isInLibraryClasses(file)
+                        || FileIndexFacade.getInstance(project).isInLibrarySource(file)
       val isWritable = file.isWritable
 
-      return when (instance(project).mode) {
+      return when (mode) {
         ReaderMode.LIBRARIES_AND_READ_ONLY -> inLibraries || !isWritable
         ReaderMode.LIBRARIES -> inLibraries
         ReaderMode.READ_ONLY -> !isWritable
diff --git a/platform/platform-resources/src/META-INF/LangExtensionPoints.xml b/platform/platform-resources/src/META-INF/LangExtensionPoints.xml
index accca6a61508..39a9526800fc 100644
--- a/platform/platform-resources/src/META-INF/LangExtensionPoints.xml
+++ b/platform/platform-resources/src/META-INF/LangExtensionPoints.xml
@@ -581,6 +581,7 @@
     <extensionPoint name="fileTypeStatisticProvider" interface="com.intellij.internal.statistic.fileTypes.FileTypeStatisticProvider" dynamic="true"/>
     <extensionPoint name="lang.directNavigationProvider" dynamic="true" interface="com.intellij.navigation.DirectNavigationProvider"/>
     <extensionPoint name="readerModeProvider" dynamic="true" interface="com.intellij.codeInsight.actions.ReaderModeProvider"/>
+    <extensionPoint name="readerModeMatcher" dynamic="true" interface="com.intellij.codeInsight.actions.ReaderModeMatcher"/>
   </extensionPoints>
 </idea-plugin>