diff --git a/misc/build_helpers/show-tool-versions.py b/misc/build_helpers/show-tool-versions.py
index a6c70f838..981f606b3 100644
--- a/misc/build_helpers/show-tool-versions.py
+++ b/misc/build_helpers/show-tool-versions.py
@@ -96,3 +96,4 @@ print_py_pkg_ver('coverage')
 print_py_pkg_ver('trialcoverage')
 print_py_pkg_ver('setuptools_trial')
 print_py_pkg_ver('pyflakes')
+print_py_pkg_ver('zope.interface')