diff --git a/.circleci/config.yml b/.circleci/config.yml
index f04e05ec0..dae69048a 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -94,8 +94,9 @@ workflows:
           {}
 
       - "integration":
-          # Run even the slow integration tests here.
-          tox-args: "--runslow"
+          # Run even the slow integration tests here.  We need the `--` to
+          # sneak past tox and get to pytest.
+          tox-args: "-- --runslow"
           requires:
             # If the unit test suite doesn't pass, don't bother running the
             # integration tests.