diff --git a/ns2-stat/Cargo.toml b/ns2-stat/Cargo.toml
index ce34b82..24b5c20 100644
--- a/ns2-stat/Cargo.toml
+++ b/ns2-stat/Cargo.toml
@@ -8,5 +8,7 @@ license = "MIT"
 
 [dependencies]
 serde = { version = "1.0", features = ["derive"] }
-serde_json = "1.0"
 serde_repr = "0.1"
+
+[dev-dependencies]
+serde_json = "1.0"