diff --git a/python/src/META-INF/python-core.xml b/python/src/META-INF/python-core.xml
index 476948f3a9bc..12e677ff5852 100644
--- a/python/src/META-INF/python-core.xml
+++ b/python/src/META-INF/python-core.xml
@@ -560,6 +560,8 @@
 
     <!-- typing -->
     <multiHostInjector implementation="com.jetbrains.python.codeInsight.PyTypingAnnotationInjector"/>
+    <lang.parserDefinition language="PythonStub" implementationClass="com.jetbrains.python.pyi.PyiParserDefinition"/>
+    <fileTypeFactory implementation="com.jetbrains.python.pyi.PyiFileTypeFactory"/>
 
     <lang.inspectionSuppressor language="Python" implementationClass="com.jetbrains.python.inspections.PyInspectionsSuppressor"/>
   </extensions>
diff --git a/python/src/com/jetbrains/python/pyi/PyiFile.java b/python/src/com/jetbrains/python/pyi/PyiFile.java
index 52e4f05c7af9..a83c3de08872 100644
--- a/python/src/com/jetbrains/python/pyi/PyiFile.java
+++ b/python/src/com/jetbrains/python/pyi/PyiFile.java
@@ -15,16 +15,24 @@
  */
 package com.jetbrains.python.pyi;
 
+import com.intellij.openapi.fileTypes.FileType;
 import com.intellij.psi.FileViewProvider;
 import com.jetbrains.python.psi.LanguageLevel;
 import com.jetbrains.python.psi.impl.PyFileImpl;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * @author vlan
  */
 public class PyiFile extends PyFileImpl {
   public PyiFile(FileViewProvider viewProvider) {
-    super(viewProvider);
+    super(viewProvider, PyiLanguageDialect.getInstance());
+  }
+
+  @NotNull
+  @Override
+  public FileType getFileType() {
+    return PyiFileType.INSTANCE;
   }
 
   @Override
diff --git a/python/src/com/jetbrains/python/pyi/PyiFileElementType.java b/python/src/com/jetbrains/python/pyi/PyiFileElementType.java
new file mode 100644
index 000000000000..d05f0793ecf9
--- /dev/null
+++ b/python/src/com/jetbrains/python/pyi/PyiFileElementType.java
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2000-2015 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 com.jetbrains.python.pyi;
+
+import com.intellij.lang.Language;
+import com.jetbrains.python.psi.PyFileElementType;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @author vlan
+ */
+public class PyiFileElementType extends PyFileElementType {
+  protected PyiFileElementType(Language language) {
+    super(language);
+  }
+
+  @NotNull
+  @Override
+  public String getExternalId() {
+    return "PythonStub.FILE";
+  }
+}
diff --git a/python/src/com/jetbrains/python/pyi/PyiFileType.java b/python/src/com/jetbrains/python/pyi/PyiFileType.java
new file mode 100644
index 000000000000..8d629d4951e2
--- /dev/null
+++ b/python/src/com/jetbrains/python/pyi/PyiFileType.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2000-2015 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 com.jetbrains.python.pyi;
+
+import com.jetbrains.python.PythonFileType;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @author vlan
+ */
+public class PyiFileType extends PythonFileType {
+  public static PythonFileType INSTANCE = new PyiFileType();
+
+  protected PyiFileType() {
+    super(new PyiLanguageDialect());
+  }
+
+  @NotNull
+  @Override
+  public String getName() {
+    return PyiLanguageDialect.ID;
+  }
+
+  @NotNull
+  @Override
+  public String getDescription() {
+    return "Python stub";
+  }
+
+  @NotNull
+  @Override
+  public String getDefaultExtension() {
+    return "pyi";
+  }
+}
diff --git a/python/src/com/jetbrains/python/pyi/PyiFileTypeFactory.java b/python/src/com/jetbrains/python/pyi/PyiFileTypeFactory.java
new file mode 100644
index 000000000000..52b4c066e8c1
--- /dev/null
+++ b/python/src/com/jetbrains/python/pyi/PyiFileTypeFactory.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2000-2015 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 com.jetbrains.python.pyi;
+
+import com.intellij.openapi.fileTypes.FileTypeConsumer;
+import com.intellij.openapi.fileTypes.FileTypeFactory;
+import com.jetbrains.python.PythonFileType;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @author vlan
+ */
+public class PyiFileTypeFactory extends FileTypeFactory {
+  @Override
+  public void createFileTypes(@NotNull FileTypeConsumer consumer) {
+    final PythonFileType instance = PyiFileType.INSTANCE;
+    consumer.consume(instance, instance.getDefaultExtension());
+  }
+}
diff --git a/python/src/com/jetbrains/python/pyi/PyiLanguageDialect.java b/python/src/com/jetbrains/python/pyi/PyiLanguageDialect.java
new file mode 100644
index 000000000000..38b07d0258d2
--- /dev/null
+++ b/python/src/com/jetbrains/python/pyi/PyiLanguageDialect.java
@@ -0,0 +1,34 @@
+/*
+ * Copyright 2000-2015 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 com.jetbrains.python.pyi;
+
+import com.intellij.lang.Language;
+import com.jetbrains.python.PythonLanguage;
+
+/**
+ * @author vlan
+ */
+public class PyiLanguageDialect extends Language {
+  public static final String ID = "PythonStub";
+
+  protected PyiLanguageDialect() {
+    super(PythonLanguage.getInstance(), ID);
+  }
+
+  public static PyiLanguageDialect getInstance() {
+    return (PyiLanguageDialect)PyiFileType.INSTANCE.getLanguage();
+  }
+}
diff --git a/python/src/com/jetbrains/python/pyi/PyiParserDefinition.java b/python/src/com/jetbrains/python/pyi/PyiParserDefinition.java
index ff3c9f5479a7..a62a6a7762c2 100644
--- a/python/src/com/jetbrains/python/pyi/PyiParserDefinition.java
+++ b/python/src/com/jetbrains/python/pyi/PyiParserDefinition.java
@@ -17,14 +17,22 @@ package com.jetbrains.python.pyi;
 
 import com.intellij.psi.FileViewProvider;
 import com.intellij.psi.PsiFile;
+import com.intellij.psi.tree.IFileElementType;
 import com.jetbrains.python.PythonParserDefinition;
 
 /**
  * @author vlan
  */
 public class PyiParserDefinition extends PythonParserDefinition {
+  public static final IFileElementType PYTHON_STUB_FILE = new PyiFileElementType(PyiLanguageDialect.getInstance());
+
   @Override
   public PsiFile createFile(FileViewProvider viewProvider) {
     return new PyiFile(viewProvider);
   }
+
+  @Override
+  public IFileElementType getFileNodeType() {
+    return PYTHON_STUB_FILE;
+  }
 }
diff --git a/python/testData/pyi/resolve/classInsidePyiFile/ClassInsidePyiFile.pyi b/python/testData/pyi/resolve/classInsidePyiFile/ClassInsidePyiFile.pyi
new file mode 100644
index 000000000000..724f1150f250
--- /dev/null
+++ b/python/testData/pyi/resolve/classInsidePyiFile/ClassInsidePyiFile.pyi
@@ -0,0 +1,6 @@
+class C:
+    def f() -> None: ...
+
+
+def g() -> C: ...
+#          <ref>
diff --git a/python/testSrc/com/jetbrains/python/fixtures/PyMultiFileResolveTestCase.java b/python/testSrc/com/jetbrains/python/fixtures/PyMultiFileResolveTestCase.java
index e3279805a97f..936e2abfdc92 100644
--- a/python/testSrc/com/jetbrains/python/fixtures/PyMultiFileResolveTestCase.java
+++ b/python/testSrc/com/jetbrains/python/fixtures/PyMultiFileResolveTestCase.java
@@ -63,7 +63,7 @@ public abstract class PyMultiFileResolveTestCase extends PyResolveTestCase {
   protected PsiFile prepareFile() {
     prepareTestDirectory();
     VirtualFile sourceFile = null;
-    for (String ext : new String[]{".py", ".pyx"}) {
+    for (String ext : new String[]{".py", ".pyx", ".pyi"}) {
       final String fileName = myTestFileName != null ? myTestFileName : getTestName(false) + ext;
       sourceFile = myFixture.findFileInTempDir(fileName);
       if (sourceFile != null) {
diff --git a/python/testSrc/com/jetbrains/python/pyi/PyiResolveTest.java b/python/testSrc/com/jetbrains/python/pyi/PyiResolveTest.java
new file mode 100644
index 000000000000..ff99d0803fd3
--- /dev/null
+++ b/python/testSrc/com/jetbrains/python/pyi/PyiResolveTest.java
@@ -0,0 +1,34 @@
+/*
+ * Copyright 2000-2015 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 com.jetbrains.python.pyi;
+
+import com.jetbrains.python.PythonTestUtil;
+import com.jetbrains.python.fixtures.PyMultiFileResolveTestCase;
+import com.jetbrains.python.psi.PyClass;
+
+/**
+ * @author vlan
+ */
+public class PyiResolveTest extends PyMultiFileResolveTestCase {
+  @Override
+  protected String getTestDataPath() {
+    return PythonTestUtil.getTestDataPath() + "/pyi/resolve";
+  }
+
+  public void testClassInsidePyiFile() {
+    assertResolvesTo(PyClass.class, "C");
+  }
+}