diff --git a/dev-requirements.txt b/dev-requirements.txt
index 7b33738..259022d 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -2,4 +2,5 @@ pytest
 hypothesis
 flake8
 autopep8
-sympy
\ No newline at end of file
+sympy
+numpy