diff --git a/object-file.c b/object-file.c
index 4047c5f372b90e..5e7a90a845ce08 100644
--- a/object-file.c
+++ b/object-file.c
@@ -2862,6 +2862,13 @@ struct oidtree *odb_loose_cache(struct object_directory *odb,
 	return odb->loose_objects_cache;
 }
 
+void odb_loose_cache_add_new_oid(struct object_directory *odb,
+				 const struct object_id *oid)
+{
+	struct oidtree *cache = odb_loose_cache(odb, oid);
+	append_loose_object(oid, NULL, cache);
+}
+
 void odb_clear_loose_cache(struct object_directory *odb)
 {
 	oidtree_clear(odb->loose_objects_cache);
diff --git a/object-store.h b/object-store.h
index de48c9a78d76b1..7e57c73fbe4e32 100644
--- a/object-store.h
+++ b/object-store.h
@@ -94,6 +94,14 @@ void restore_primary_odb(struct object_directory *restore_odb, const char *old_p
 struct oidtree *odb_loose_cache(struct object_directory *odb,
 				  const struct object_id *oid);
 
+/*
+ * Add a new object to the loose object cache (possibly after the
+ * cache was populated).  This might be used after dynamically
+ * fetching a missing object.
+ */
+void odb_loose_cache_add_new_oid(struct object_directory *odb,
+				 const struct object_id *oid);
+
 /* Empty the loose object cache for the specified object directory. */
 void odb_clear_loose_cache(struct object_directory *odb);