diff --git a/docs/_static/.gitkeep b/docs/_static/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/setup.py b/setup.py
index 6f6f3c7..89291fe 100644
--- a/setup.py
+++ b/setup.py
@@ -23,6 +23,12 @@ setup(
 
     python_requires=">= 3.2",
     install_requires=[],
+    extras_require={
+        "docs": [
+            "sphinx",
+            "sphinx_rtd_theme",
+        ],
+    },
     entry_points={},
 
     platforms=["all"],