diff --git a/common/system_state.cc b/common/system_state.cc
new file mode 100644
index 0000000..40bf760
--- /dev/null
+++ b/common/system_state.cc
@@ -0,0 +1,23 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/common/system_state.h"
+
+namespace chromeos_update_engine {
+
+std::unique_ptr<SystemState> SystemState::g_instance_;
+
+}  // namespace chromeos_update_engine