diff --git a/var/spack/repos/builtin/packages/py-py-spy/package.py b/var/spack/repos/builtin/packages/py-py-spy/package.py
index ec11a6a7eef..f7c048af109 100644
--- a/var/spack/repos/builtin/packages/py-py-spy/package.py
+++ b/var/spack/repos/builtin/packages/py-py-spy/package.py
@@ -17,3 +17,4 @@ class PyPySpy(PythonPackage):
     # Need to figure out how to manage these with Spack once we have a
     # CargoPackage base class.
     depends_on('rust', type='build')
+    depends_on('unwind')