diff --git a/setup.py b/setup.py
index 39d3a59..76df4f7 100644
--- a/setup.py
+++ b/setup.py
@@ -1,5 +1,5 @@
 # -*- coding: utf-8 -*-
-from distutils.core import setup
+from setuptools import setup
 
 packages = \
 ['poetry',
@@ -38,14 +38,16 @@ package_data = \
 
 install_requires = \
 ['cachecontrol[filecache]>=0.12.4,<0.13.0',
- 'cachy>=0.2,<0.3',
+ 'cachy>=0.2',
  'cleo>=0.6.7,<0.7.0',
  'html5lib>=1.0,<2.0',
  'jsonschema>=3.0a3,<4.0',
+ 'lockfile',
+ 'pip',
  'pkginfo>=1.4,<2.0',
  'pyparsing>=2.2,<3.0',
- 'pyrsistent>=0.14.2,<0.15.0',
- 'requests-toolbelt>=0.8.0,<0.9.0',
+ 'pyrsistent>=0.14.2',
+ 'requests-toolbelt',
  'requests>=2.18,<3.0',
  'shellingham>=1.1,<2.0',
  'tomlkit>=0.5.1,<0.6.0']