diff --git a/src/secure/signed.rs b/src/secure/signed.rs
index 2390f17..954866e 100644
--- a/src/secure/signed.rs
+++ b/src/secure/signed.rs
@@ -33,7 +33,7 @@ impl<'a> SignedJar<'a> {
     /// Signs the cookie's value providing integrity and authenticity.
     fn sign_cookie(&self, cookie: &mut Cookie) {
         // Compute HMAC-SHA256 of the cookie's value.
-        let mut mac = Hmac::<Sha256>::new_varkey(&self.key).expect("good key");
+        let mut mac = Hmac::<Sha256>::new_from_slice(&self.key).expect("good key");
         mac.update(cookie.value().as_bytes());
 
         // Cookie's new value is [MAC | original-value].
@@ -55,7 +55,7 @@ impl<'a> SignedJar<'a> {
         let digest = base64::decode(digest_str).map_err(|_| "bad base64 digest")?;
 
         // Perform the verification.
-        let mut mac = Hmac::<Sha256>::new_varkey(&self.key).expect("good key");
+        let mut mac = Hmac::<Sha256>::new_from_slice(&self.key).expect("good key");
         mac.update(value.as_bytes());
         mac.verify(&digest)
             .map(|_| value.to_string())