diff --git a/tools/ci/backend b/tools/ci/backend
index 96e4208d38..1c698fcdd7 100755
--- a/tools/ci/backend
+++ b/tools/ci/backend
@@ -8,7 +8,11 @@ set -x
 
 ./tools/lint --backend --no-gitlint --no-mypy  # gitlint disabled because flaky
 ./tools/test-tools
-./tools/test-backend --coverage --include-webhooks
+# We need to pass a parallel level to test-backend because CircleCI's
+# docker setup means the auto-detection logic sees the ~36 processes
+# the Docker host has, not the ~2 processes of resources we're
+# allocated.
+./tools/test-backend --coverage --include-webhooks --parallel=6
 
 # We run mypy after the backend tests so we get output from the
 # backend tests, which tend to uncover more serious problems, first.