diff --git a/ChangeLog.md b/ChangeLog.md
index dc716d9..4e80783 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,8 @@
 # Write Your Python Program - CHANGELOG
 
+* 2.2.0 (2026-03-17)
+  * Performance improvements
+  * Fix for multi-threaded environment
 * 2.1.2 (2025-12-08)
   * Fix for running a file that has the same name as a module from the stdlib
   * Fix debugger invocation #194
diff --git a/package.json b/package.json
index b4a543c..ce78a2f 100644
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
 	"displayName": "Write Your Python Program!",
 	"description": "A user friendly python environment for beginners",
 	"license": "See license in LICENSE",
-	"version": "2.1.2",
+	"version": "2.2.0",
 	"publisher": "StefanWehr",
 	"icon": "icon.png",
 	"engines": {
diff --git a/python/file-test-data/extras/multi_thread_ok.err b/python/file-test-data/extras/multi_thread_ok.err
new file mode 100644
index 0000000..e69de29
diff --git a/python/file-test-data/extras/multi_thread_ok.out b/python/file-test-data/extras/multi_thread_ok.out
new file mode 100644
index 0000000..c44a176
--- /dev/null
+++ b/python/file-test-data/extras/multi_thread_ok.out
@@ -0,0 +1,15 @@
+START
+started
+WyppTypeError: '1'
+
+Rückgabewert vom Typ `int` erwartet bei Aufruf der Funktion `foo`.
+Aber der Aufruf gibt einen Wert vom Typ `str` zurück.
+
+## Datei file-test-data/extras/multi_thread_ok.py
+## Rückgabetyp deklariert in Zeile 4:
+
+def foo(i: int) -> int:
+
+## Aufruf in Zeile 9 verursacht das fehlerhafte return:
+
+        foo(1)
diff --git a/python/file-test-data/extras/multi_thread_ok.py b/python/file-test-data/extras/multi_thread_ok.py
new file mode 100644
index 0000000..be62ebe
--- /dev/null
+++ b/python/file-test-data/extras/multi_thread_ok.py
@@ -0,0 +1,18 @@
+import wypp
+import threading
+
+def foo(i: int) -> int:
+    return str(i)
+
+def doWork():
+    try:
+        foo(1)
+    except wypp.WyppTypeError as e:
+        print(e)
+
+t = threading.Thread(target=doWork)
+print('START')
+t.start()
+print('started')
+t.join()
+