diff --git a/payload_state.h b/payload_state.h
index 56e32fd..699fc74 100644
--- a/payload_state.h
+++ b/payload_state.h
@@ -153,13 +153,7 @@
     return attempt_error_code_;
   }
 
-  bool NextPayload() override {
-    if (payload_index_ + 1 >= candidate_urls_.size())
-      return false;
-    payload_index_++;
-    url_index_ = 0;
-    return true;
-  }
+  bool NextPayload() override;
 
  private:
   enum class AttemptType {
@@ -280,6 +274,11 @@
   // of a process restart.
   void SetFullPayloadAttemptNumber(int payload_attempt_number);
 
+  // Sets the current payload index to the given value. Also persists the value
+  // being set so that we resume from the same value in case of a process
+  // restart.
+  void SetPayloadIndex(size_t payload_index);
+
   // Initializes the current URL index from the persisted state.
   void LoadUrlIndex();