diff --git a/src/error.rs b/src/error.rs
index b8f0356..6cacba6 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -334,7 +334,8 @@ impl Display for ErrorCode {
 }
 
 impl serde::de::StdError for Error {
-    fn source(&self) -> Option<&(serde::de::StdError + 'static)> {
+    #[cfg(feature = "std")]
+    fn source(&self) -> Option<&(error::Error + 'static)> {
         match self.err.code {
             ErrorCode::Io(ref err) => Some(err),
             _ => None,
diff --git a/src/io/core.rs b/src/io/core.rs
index f83f5cf..5ffea38 100644
--- a/src/io/core.rs
+++ b/src/io/core.rs
@@ -22,8 +22,6 @@ impl Debug for Error {
     }
 }
 
-impl serde::de::StdError for Error {}
-
 impl Error {
     pub(crate) fn new(kind: ErrorKind, error: &'static str) -> Error {
         let _ = kind;