diff --git a/README.md b/README.md
index 11d55e8..3dcb7f2 100644
--- a/README.md
+++ b/README.md
@@ -40,6 +40,22 @@ source env/bin/activate
 ```
 
 
+# Development
+Setup like above, and also:
+
+```
+cd plot-freely/
+source env/bin/activate
+pip install -r requirements-dev.txt
+```
+
+Then before committing new code, make sure it is enprettified:
+
+```
+black polar-plot
+```
+
+
 # See Also
 
 CygnusRFI
diff --git a/polar-plot b/polar-plot
index 7a530d8..5a8d88b 100755
--- a/polar-plot
+++ b/polar-plot
@@ -27,7 +27,6 @@
 # Example:
 # polar_plot
 
-
 import numpy as np
 import matplotlib.pyplot as plt
 
@@ -44,4 +43,3 @@ if __name__ == "__main__":
     ax.set_ylim(0.0, 90.0)
 
     plt.show()
-
diff --git a/requirements-dev.txt b/requirements-dev.txt
new file mode 100644
index 0000000..7e66a17
--- /dev/null
+++ b/requirements-dev.txt
@@ -0,0 +1 @@
+black