diff --git a/.github/requirements-old.txt b/.github/requirements-old.txt
index f8bd6ab..753ec32 100644
--- a/.github/requirements-old.txt
+++ b/.github/requirements-old.txt
@@ -1,6 +1,5 @@
 # Ensure changes to these dependencies are reflected in pyproject.toml
-attrs==24.1.0
-cattrs==24.1.0
+attrs==23.1.0
 matplotlib==3.9.0
 numpy==2.0.0
 scipy==1.13.0
diff --git a/pyproject.toml b/pyproject.toml
index d6c3f21..23787d2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,8 +30,7 @@ classifiers = [
 ]
 dependencies = [
     # Ensure changes to these dependencies are reflected in .github/requirements-old.txt
-    "attrs>=24.1.0",
-    "cattrs>=24.1.0",
+    "attrs>=23.1.0",
     "matplotlib>=3.9.0",
     "numpy>=2.0.0",
     "scipy>=1.13.0",