diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index 9ff96fe..8a2ded2 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -9,7 +9,7 @@ version: 2
 build:
   os: ubuntu-20.04
   tools:
-    python: "3.8"
+    python: "3.7"
     # You can also specify other tool versions:
     # nodejs: "16"
     # rust: "1.55"
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2aa7164..9badbda 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,7 @@ using in a reinforcement learning (RL) context)
 - More robust attribute handling for various objects
 
 ### Changed
+- Allow earlier version of numpy (v1.21 insead of v1.22), which in turn allows Python 3.7 instead of 3.8
 - New format for storing and loading named instances, and better documentation
 - ``newsvendor.newsvendor_explicit()`` parameter renamed to ``revenue`` from ``selling_revenue`` for consistency
 
diff --git a/requirements.txt b/requirements.txt
index 3a72cb9..88f9efe 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,7 +2,7 @@ build==0.0.2
 jsonpickle==1.0
 matplotlib==2.0
 networkx==2.0
-numpy==1.22
+numpy==1.21
 scipy==1.6.0
 setuptools==49.6
 sphinx==4.5.0
diff --git a/setup.cfg b/setup.cfg
index bfb1ffe..bf53b3e 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -27,7 +27,7 @@ install_requires =
     jsonpickle>=1.0
     matplotlib>=2.0
     networkx>=2.0
-    numpy>=1.22
+    numpy>=1.21
     scipy>=1.6.0
     setuptools>=49.6
     sphinx==4.5.0
diff --git a/tests/settings.py b/tests/settings.py
index 988a505..7eb43d2 100644
--- a/tests/settings.py
+++ b/tests/settings.py
@@ -2,4 +2,4 @@
 
 # Set to True to run all tests, even those that are normally skipped because
 # they are slow.
-RUN_ALL_TESTS = False
\ No newline at end of file
+RUN_ALL_TESTS = True
\ No newline at end of file