diff --git a/.git_archival.txt b/.git_archival.txt
new file mode 100644
index 0000000..95cb3ee
--- /dev/null
+++ b/.git_archival.txt
@@ -0,0 +1 @@
+ref-names: $Format:%D$
diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..00a7b00
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1 @@
+.git_archival.txt  export-subst
diff --git a/proxmin/nmf.py b/proxmin/nmf.py
index 28615a3..05e6919 100644
--- a/proxmin/nmf.py
+++ b/proxmin/nmf.py
@@ -61,7 +61,7 @@ def step_pgm(*X, it=None, W=1):
         step_A, step_S
     """
     A, S = X
-    if W is 1:
+    if W == 1:
         return step_A(A, S), step_S(A, S)
     else:
         C, K = A.shape
diff --git a/setup.py b/setup.py
index 140c8a8..005a401 100644
--- a/setup.py
+++ b/setup.py
@@ -1,11 +1,6 @@
-from setuptools import setup
+from setuptools import setup, find_packages
 import os
 
-packages = []
-for root, dirs, files in os.walk('.'):
-    if not root.startswith('./build') and '__init__.py' in files:
-        packages.append(root[2:])
-
 long_description = open('README.md').read()
 
 setup(
@@ -13,9 +8,9 @@
     description = 'Proximal methods for constrained optimization',
     long_description = long_description,
     long_description_content_type='text/markdown',
-    packages = packages,
+    packages=find_packages(),
     include_package_data=False,
-    version = '0.6.9',
+    use_scm_version=True,
     license='MIT',
     author = 'Peter Melchior, Fred Moolekamp',
     author_email = 'peter.m.melchior@gmail.com',
@@ -30,5 +25,6 @@
         "Topic :: Scientific/Engineering :: Information Analysis"
     ],
     keywords = ['optimization', 'constrained optimization', 'proximal algorithms', 'data analysis', 'non-negative matrix factorization'],
-    requires=['numpy','scipy']
+    setup_requires=['setuptools_scm', 'setuptools_scm_git_archive'],
+    install_requires=['numpy','scipy'],
 )