diff --git a/quic/core/crypto/quic_hkdf.h b/quic/core/crypto/quic_hkdf.h
index c57b894..09006ee 100644
--- a/quic/core/crypto/quic_hkdf.h
+++ b/quic/core/crypto/quic_hkdf.h
@@ -5,6 +5,8 @@
 #ifndef QUICHE_QUIC_CORE_CRYPTO_QUIC_HKDF_H_
 #define QUICHE_QUIC_CORE_CRYPTO_QUIC_HKDF_H_
 
+#include <vector>
+
 #include "net/third_party/quiche/src/quic/platform/api/quic_export.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_string_piece.h"