diff --git a/pyebsdindex/__init__.py b/pyebsdindex/__init__.py
index 897a995..52a7f0f 100644
--- a/pyebsdindex/__init__.py
+++ b/pyebsdindex/__init__.py
@@ -7,7 +7,7 @@
 ]
 __description__ = "Python based tool for Radon based EBSD indexing"
 __name__ = "pyebsdindex"
-__version__ = "0.3.9"
+__version__ = "0.3.9.1"
 
 
 # Try to import only once - also will perform check that at least one GPU is found.
diff --git a/setup.py b/setup.py
index a5e0e9c..3a551e0 100644
--- a/setup.py
+++ b/setup.py
@@ -96,6 +96,7 @@
         "numpy",
         "numba>=0.55.1",
         "scipy",
+        "psutil"
     ],
     # Files to include when distributing package (see also MANIFEST.in)
     packages=find_packages(),