diff --git a/bin/steps/pip-uninstall b/bin/steps/pip-uninstall
index 312d425010c2a268f4d8b830f4a6cf97ddf0481b..49124f174d34afc90e67262d0b7b72fe92fd6c96 100755
--- a/bin/steps/pip-uninstall
+++ b/bin/steps/pip-uninstall
@@ -3,7 +3,11 @@ set +e
 bpwatch start pip_uninstall
 if [[ -f .heroku/python/requirements-declared.txt ]]; then
 
-  pip-diff --stale .heroku/python/requirements-declared.txt requirements.txt > .heroku/python/requirements-stale.txt
+  cp .heroku/python/requirements-declared.txt requirements-declared.txt
+
+  pip-diff --stale requirements-declared.txt requirements.txt > .heroku/python/requirements-stale.txt
+
+  rm -fr requirements-declared.txt
 
   if [[ -s .heroku/python/requirements-stale.txt ]]; then
     puts-step "Uninstalling stale dependencies"