diff --git a/pkgs/development/python-modules/pymc/default.nix b/pkgs/development/python-modules/pymc/default.nix
index a420212baea0..8f2ea6ee717a 100644
--- a/pkgs/development/python-modules/pymc/default.nix
+++ b/pkgs/development/python-modules/pymc/default.nix
@@ -37,6 +37,10 @@ buildPythonPackage rec {
     versioneer
   ];
 
+  pythonRelaxDeps = [
+    "pytensor"
+  ];
+
   dependencies = [
     arviz
     cachetools