diff --git a/plays/filter_plugins/filters.py b/plays/filter_plugins/filters.py
new file mode 100644
index 0000000..2b6fe46
--- /dev/null
+++ b/plays/filter_plugins/filters.py
@@ -0,0 +1,21 @@
+#!/usr/bin/env python3
+
+"""Custom filters for use in playbooks."""
+
+
+class FilterModule(object):
+    """Custom Ansible filter plugins."""
+
+    def filters(self):
+        """Filters list."""
+        return {"update_env": self.filter_update_env}
+
+    def filter_update_env(self, config, new_env):
+        """Update the config.env dictionary with new keys."""
+        if "env" not in config:
+            return config
+
+        for key, val in new_env.items():
+            config["env"][key] = val
+
+        return config
diff --git a/plays/filter_plugins/update_env.py b/plays/filter_plugins/update_env.py
deleted file mode 100644
index f798adb..0000000
--- a/plays/filter_plugins/update_env.py
+++ /dev/null
@@ -1,16 +0,0 @@
-"""Update config.env filter."""
-
-
-def filter_update_env(config, env):
-    if config.get("env", False) is False:
-        return config
-
-    for key, val in env:
-        config["env"][key] = val
-
-    return config
-
-
-class FilterModule(object):
-    def filters(self):
-        return {"update_env": filter_update_env}