diff --git a/Cargo.toml b/Cargo.toml
index c55f057..0366e41 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -40,6 +40,7 @@ gitlab = { repository = "abaumhauer/eui48", branch = "master" }
 appveyor = { repository = "abaumhauer/eui48", branch = "master", service = "github" }
 
 [features]
-default = ["rustc-serialize"]
+default = []
 disp_hexstring = []
 serde_bytes = ["serde"]
+rustc_serialize = ["rustc-serialize"]
diff --git a/src/lib.rs b/src/lib.rs
index 58dba71..33f7c70 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -681,6 +681,7 @@ mod tests {
         assert_eq!(m2, m1);
     }
 
+    #[cfg(feature = "rustc_serialize")]
     #[test]
     fn test_serialize() {
         use rustc_serialize::json;
@@ -694,6 +695,7 @@ mod tests {
         }
     }
 
+    #[cfg(feature = "rustc_serialize")]
     #[test]
     fn test_deserialize() {
         use rustc_serialize::json;
@@ -709,6 +711,7 @@ mod tests {
         }
     }
 
+    #[cfg(feature = "rustc_serialize")]
     #[test]
     fn test_serialize_roundtrip() {
         use rustc_serialize::json;