diff --git a/core/interface.go b/core/interface.go
index 4ed552e..98ca600 100644
--- a/core/interface.go
+++ b/core/interface.go
@@ -57,6 +57,7 @@ type Backend interface {
 
 	GetTrie(hash Hash) (Trie, error)
 	GetAccountTrie(stateRoot Hash, account Address) (Trie, error)
+	GetContractCode(Hash) ([]byte, error)
 
 	// ChainConfig() *params.ChainConfig
 	// Engine() consensus.Engine