diff --git a/src/odb_mempack.c b/src/odb_mempack.c
index 68db3bc32..84ed9c104 100644
--- a/src/odb_mempack.c
+++ b/src/odb_mempack.c
@@ -177,6 +177,7 @@ int git_mempack_new(git_odb_backend **out)
 
 	db->objects = git_oidmap_alloc();
 
+	db->parent.version = GIT_ODB_BACKEND_VERSION;
 	db->parent.read = &impl__read;
 	db->parent.write = &impl__write;
 	db->parent.read_header = &impl__read_header;