diff --git a/src.mk b/src.mk
index 7e4ac67c6..292d47510 100644
--- a/src.mk
+++ b/src.mk
@@ -92,6 +92,7 @@ LIB_SOURCES =                                                   \
   utilities/checkpoint/checkpoint.cc                            \
   utilities/compacted_db/compacted_db_impl.cc                   \
   utilities/document/document_db.cc                             \
+  utilities/document/json_document_builder.cc                   \
   utilities/document/json_document.cc                           \
   utilities/geodb/geodb_impl.cc                                 \
   utilities/leveldb_options/leveldb_options.cc                  \