diff --git a/constraints.txt b/constraints.txt
index e717281..5f19de0 100644
--- a/constraints.txt
+++ b/constraints.txt
@@ -1 +1,2 @@
 Django>=3.1
+django-sendmail-backend==0.1.2
diff --git a/requirements.txt b/requirements.txt
index 4f285a4..c659cd1 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,3 +2,4 @@
 
 Django
 django-autocomplete-light
+django_sendmail_backend