--- /dev/null
+package PVE::ACME::Challenge;
+
+use strict;
+use warnings;
+
+sub supported_challenge_types {
+ return {};
+}
+
+sub setup {
+ my ($class, $acme, $authorization) = @_;
+
+ die "implement me\n";
+}
+
+sub teardown {
+ my ($self) = @_;
+
+ die "implement me\n";
+}
+
+1;