diff --git a/requirements.txt b/requirements.txt
index 725760b..74d20fd 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,6 +3,7 @@ attrs~=21.2.0
 dm-tree~=0.1.1
 matplotlib~=3.3.4
 mpmath
+numpy~=1.21.5
 scipy>=0.17
 tensorflow-datasets>=4.4.0
 tensorflow-estimator>=2.3.0
diff --git a/setup.py b/setup.py
index 2d6cec9..8e25631 100644
--- a/setup.py
+++ b/setup.py
@@ -31,6 +31,7 @@ setup(
         'attrs~=21.2.0',
         'dm-tree~=0.1.1',
         'matplotlib~=3.3.4',
+        'numpy~=1.21.5',
         'scipy>=0.17',
         'tensorflow-datasets>=4.4.0',
         'tensorflow-estimator>=2.3.0',