diff --git a/Cargo.toml b/Cargo.toml
index 4a31c70..4b3d8db 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,6 +9,7 @@ edition = "2018"
 [dependencies]
 serde = { version = "1.0.117", optional = true }
 serde_derive = { version = "1.0.117", optional = true }
+serde_json = "1.0"
 once_cell = "1.5.2"
 
 [features]