diff --git a/graphene_django/debug/middleware.py b/graphene_django/debug/middleware.py
index 5b9d82e..d3052a1 100644
--- a/graphene_django/debug/middleware.py
+++ b/graphene_django/debug/middleware.py
@@ -9,32 +9,32 @@ from .types import DjangoDebug
 
 class DjangoDebugContext:
     def __init__(self):
-        self.debug_promise = None
-        self.promises = []
+        self.debug_result = None
+        self.results = []
         self.object = DjangoDebug(sql=[], exceptions=[])
         self.enable_instrumentation()
 
-    def get_debug_promise(self):
-        if not self.debug_promise:
-            self.debug_promise = Promise.all(self.promises)
-            self.promises = []
-        return self.debug_promise.then(self.on_resolve_all_promises).get()
+    def get_debug_result(self):
+        if not self.debug_result:
+            self.debug_result = self.results
+            self.results = []
+        return self.on_resolve_all_results()
 
     def on_resolve_error(self, value):
         if hasattr(self, "object"):
             self.object.exceptions.append(wrap_exception(value))
-        return Promise.reject(value)
+        return value
 
-    def on_resolve_all_promises(self, values):
-        if self.promises:
-            self.debug_promise = None
-            return self.get_debug_promise()
+    def on_resolve_all_results(self):
+        if self.results:
+            self.debug_result = None
+            return self.get_debug_result()
         self.disable_instrumentation()
         return self.object
 
-    def add_promise(self, promise):
-        if self.debug_promise:
-            self.promises.append(promise)
+    def add_result(self, result):
+        if self.debug_result:
+            self.results.append(result)
 
     def enable_instrumentation(self):
         # This is thread-safe because database connections are thread-local.
@@ -62,10 +62,10 @@ class DjangoDebugMiddleware:
                     )
                 )
         if info.schema.get_type("DjangoDebug") == info.return_type:
-            return context.django_debug.get_debug_promise()
+            return context.django_debug.get_debug_result()
         try:
-            promise = next(root, info, **args)
+            result = next(root, info, **args)
         except Exception as e:
             return context.django_debug.on_resolve_error(e)
-        context.django_debug.add_promise(promise)
-        return promise
+        context.django_debug.add_result(result)
+        return result
diff --git a/tox.ini b/tox.ini
index 47fd1e5..285d046 100644
--- a/tox.ini
+++ b/tox.ini
@@ -23,6 +23,7 @@ passenv = *
 usedevelop = True
 setenv =
     DJANGO_SETTINGS_MODULE=examples.django_test_settings
+    PYTHONPATH=.
 deps =
     -e.[test]
     psycopg2-binary