Updated backend

pytest.ini

@@ -0,0 +1,16 @@
+[pytest]
+testpaths = tests
+
+# Warnings are errors. A DeprecationWarning is a change that will break the
+# build later, and the only reliable time to deal with one is when it first
+# appears - once a few are tolerated, the new one is invisible in the noise.
+#
+# When a dependency starts warning about something you cannot fix yet, add a
+# narrow ignore here rather than relaxing this line, e.g.:
+#
+#   ignore:some message regex:DeprecationWarning:the_package.*
+#
+# Keep each ignore as specific as the warning it silences, so it stops applying
+# once the dependency is fixed.
+filterwarnings =
+    error