diff --git a/requirements/base.txt b/requirements/base.txt
index e3702db..0444250 100644
--- a/requirements/base.txt
+++ b/requirements/base.txt
@@ -2,3 +2,7 @@
 # ------------------------------------------------------------------------------
 django >=3.0,<3.1  # https://www.djangoproject.com/
 django-environ ==0.4.5  # https://github.com/joke2k/django-environ
+
+# PHP
+# ------------------------------------------------------------------------------
+phpserialize