diff --git a/sequencer.h b/sequencer.h
index ec13b67..4f616c6 100644
--- a/sequencer.h
+++ b/sequencer.h
@@ -75,4 +75,9 @@ int update_head_with_reflog(const struct commit *old_head,
 			    struct strbuf *err);
 void commit_post_rewrite(const struct commit *current_head,
 			 const struct object_id *new_head);
+
+#define SUMMARY_INITIAL_COMMIT   (1 << 0)
+#define SUMMARY_SHOW_AUTHOR_DATE (1 << 1)
+void print_commit_summary(const char *prefix, const struct object_id *oid,
+			  unsigned int flags);
 #endif