diff --git a/app/helper.py b/app/helper.py
index 39e01f9..abbe800 100644
--- a/app/helper.py
+++ b/app/helper.py
@@ -88,7 +88,7 @@ class VirtualenvOperation(object):
             command = f"pip install {package_name}"
         else:
             with open(os.path.join(path, "requirements.txt"), "w") as f:
-                subprocess.check_output("pipenv run pip freeze".split(), cwd=path, stdout=f)
+                subprocess.Popen("pipenv run pip freeze".split(), cwd=path, stdout=f)
             command = f"pip install -r requirements.txt"
         try:
             output = subprocess.check_output(command.split(), cwd=path)