diff --git a/packages/google-cloud-ndb/noxfile.py b/packages/google-cloud-ndb/noxfile.py
index b457368bb75f..6bd692e74290 100644
--- a/packages/google-cloud-ndb/noxfile.py
+++ b/packages/google-cloud-ndb/noxfile.py
@@ -189,11 +189,13 @@ def cover(session):
     session.run("coverage", "erase")
 
 
+@nox.session(python=ALL_INTERPRETERS)
 def old_emulator_system(session):
     emulator_args = ["gcloud", "beta", "emulators", "datastore", "start"]
     _run_emulator(session, emulator_args)
 
 
+@nox.session(python=ALL_INTERPRETERS)
 def emulator_system(session):
     emulator_args = [
         "gcloud",