diff --git a/var/spack/repos/builtin/packages/py-pyrsistent/package.py b/var/spack/repos/builtin/packages/py-pyrsistent/package.py
index 765760efe5..6732c14481 100644
--- a/var/spack/repos/builtin/packages/py-pyrsistent/package.py
+++ b/var/spack/repos/builtin/packages/py-pyrsistent/package.py
@@ -14,8 +14,11 @@ class PyPyrsistent(PythonPackage):
     homepage = "https://github.com/tobgu/pyrsistent/"
     pypi = "pyrsistent/pyrsistent-0.15.7.tar.gz"
 
+    version('0.18.0', sha256='773c781216f8c2900b42a7b638d5b517bb134ae1acbebe4d1e8f1f41ea60eb4b')
     version('0.15.7', sha256='cdc7b5e3ed77bed61270a47d35434a30617b9becdf2478af76ad2c6ade307280')
 
     depends_on('python@2.7:2.8,3.5:', type=('build', 'link', 'run'))
+    depends_on('python@3.6:', type=('build', 'link', 'run'), when='@0.18.0:')
     depends_on('py-setuptools', type='build')
-    depends_on('py-six', type=('build', 'run'))
+    depends_on('py-setuptools@42:', type='build', when='@0.18.0:')
+    depends_on('py-six', type=('build', 'run'), when='@:0.17')