diff --git a/ondevice-signing/SigningKey.h b/ondevice-signing/SigningKey.h
new file mode 100644
index 0000000..89294fc
--- /dev/null
+++ b/ondevice-signing/SigningKey.h
@@ -0,0 +1,29 @@
+/*
+ * 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.
+ */
+
+#pragma once
+
+#include <android-base/macros.h>
+#include <android-base/result.h>
+
+class SigningKey {
+  public:
+    virtual ~SigningKey(){};
+    /* Sign a message with an initialized signing key */
+    virtual android::base::Result<std::string> sign(const std::string& message) const = 0;
+    /* Retrieve the associated public key */
+    virtual android::base::Result<std::vector<uint8_t>> getPublicKey() const = 0;
+};