diff --git a/var/spack/repos/builtin/packages/py-cfgv/package.py b/var/spack/repos/builtin/packages/py-cfgv/package.py
index 1603be7caa6..73037c8beff 100644
--- a/var/spack/repos/builtin/packages/py-cfgv/package.py
+++ b/var/spack/repos/builtin/packages/py-cfgv/package.py
@@ -12,8 +12,10 @@ class PyCfgv(PythonPackage):
     homepage = "https://github.com/asottile/cfgv/"
     pypi = "cfgv/cfgv-2.0.1.tar.gz"
 
+    version("3.3.1", sha256="f5a830efb9ce7a445376bb66ec94c638a9787422f96264c98edc6bdeed8ab736")
     version("2.0.1", sha256="edb387943b665bf9c434f717bf630fa78aecd53d5900d2e05da6ad6048553144")
 
+    depends_on("python@3.6.1:", when="@3.1:", type=("build", "run"))
     depends_on("python@2.7:2.8,3.4:", type=("build", "run"))
     depends_on("py-setuptools", type="build")
-    depends_on("py-six", type=("build", "run"))
+    depends_on("py-six", when="@:2", type=("build", "run"))