diff --git a/python/requirements.txt b/python/requirements.txt
index 90505f8..7181cc9 100644
--- a/python/requirements.txt
+++ b/python/requirements.txt
@@ -1,4 +1,3 @@
-Cython>=0.22
 cmdstanpy>=1.0.4
 numpy>=1.15.4
 pandas>=1.0.4
diff --git a/python_shim/requirements.txt b/python_shim/requirements.txt
index 27e627d..79b4658 100644
--- a/python_shim/requirements.txt
+++ b/python_shim/requirements.txt
@@ -1 +1 @@
-prophet~=1.0.1
+prophet
diff --git a/python_shim/setup.py b/python_shim/setup.py
index 2976a81..a2b8df9 100644
--- a/python_shim/setup.py
+++ b/python_shim/setup.py
@@ -5,7 +5,6 @@
 
 from setuptools import setup, find_packages
 
-
 with open('README.md', 'r', encoding='utf-8') as f:
     long_description = f.read()