diff --git a/bindings/cashu-ffi/src/cashu.udl b/bindings/cashu-ffi/src/cashu.udl
index 662d6684..e128c0e4 100644
--- a/bindings/cashu-ffi/src/cashu.udl
+++ b/bindings/cashu-ffi/src/cashu.udl
@@ -22,6 +22,11 @@ interface Amount {
  	sequence<Amount> split();
 };
 
+interface Secret {
+	constructor();
+	sequence<u8> as_bytes();	
+};
+
 
 interface PublicKey {
     [Throws=CashuError, Name=from_hex]
@@ -43,9 +48,9 @@ interface BlindedMessage {
 };
 
 interface Proof {
-	constructor(Amount amount, string secret, PublicKey c, string? id);
+	constructor(Amount amount, Secret secret, PublicKey c, string? id);
 	Amount amount();
-	string secret();
+	Secret secret();
 	PublicKey c();
 	string? id();
 };
@@ -58,9 +63,9 @@ interface BlindedSignature {
 };
 
 interface MintProof {
-	constructor(Amount? amount, string secret, PublicKey? c, string? id);
+	constructor(Amount? amount, Secret secret, PublicKey? c, string? id);
 	Amount? amount();
-	string secret();
+	Secret secret();
 	PublicKey? c();
 	string? id();
 	
@@ -91,7 +96,7 @@ interface BlindedMessages {
     [Throws=CashuError, Name=blank]
 	constructor(Amount fee_reserve);
 	sequence<BlindedMessage> blinded_messages();
-	sequence<string> secrets();
+	sequence<Secret> secrets();
 	sequence<SecretKey> rs();
 	sequence<Amount> amounts();
 };
diff --git a/bindings/cashu-ffi/src/lib.rs b/bindings/cashu-ffi/src/lib.rs
index 7045ba76..247755de 100644
--- a/bindings/cashu-ffi/src/lib.rs
+++ b/bindings/cashu-ffi/src/lib.rs
@@ -27,6 +27,7 @@ mod ffi {
     pub use crate::nuts::nut09::{MintInfo, MintVersion};
     pub use crate::types::amount::Amount;
     pub use crate::types::Bolt11Invoice;
+    pub use crate::types::Secret;
 
     pub use cashu::types::InvoiceStatus;
 
diff --git a/bindings/cashu-ffi/src/nuts/nut00/blinded_messages.rs b/bindings/cashu-ffi/src/nuts/nut00/blinded_messages.rs
index d6877323..66638850 100644
--- a/bindings/cashu-ffi/src/nuts/nut00/blinded_messages.rs
+++ b/bindings/cashu-ffi/src/nuts/nut00/blinded_messages.rs
@@ -2,7 +2,7 @@ use std::{ops::Deref, sync::Arc};
 
 use cashu::nuts::nut00::wallet::BlindedMessages as BlindedMessagesSdk;
 
-use crate::{error::Result, Amount, BlindedMessage, SecretKey};
+use crate::{error::Result, Amount, BlindedMessage, Secret, SecretKey};
 
 pub struct BlindedMessages {
     inner: BlindedMessagesSdk,
@@ -37,8 +37,13 @@ impl BlindedMessages {
             .collect()
     }
 
-    pub fn secrets(&self) -> Vec<String> {
-        self.inner.secrets.clone()
+    pub fn secrets(&self) -> Vec<Arc<Secret>> {
+        self.inner
+            .secrets
+            .clone()
+            .into_iter()
+            .map(|s| Arc::new(s.into()))
+            .collect()
     }
 
     pub fn rs(&self) -> Vec<Arc<SecretKey>> {
diff --git a/bindings/cashu-ffi/src/nuts/nut00/proof.rs b/bindings/cashu-ffi/src/nuts/nut00/proof.rs
index 17c67a69..2a3ab6a1 100644
--- a/bindings/cashu-ffi/src/nuts/nut00/proof.rs
+++ b/bindings/cashu-ffi/src/nuts/nut00/proof.rs
@@ -2,7 +2,7 @@ use std::{ops::Deref, sync::Arc};
 
 use cashu::nuts::nut00::Proof as ProofSdk;
 
-use crate::{Amount, PublicKey};
+use crate::{types::Secret, Amount, PublicKey};
 
 pub struct Proof {
     inner: ProofSdk,
@@ -16,11 +16,16 @@ impl Deref for Proof {
 }
 
 impl Proof {
-    pub fn new(amount: Arc<Amount>, secret: String, c: Arc<PublicKey>, id: Option<String>) -> Self {
+    pub fn new(
+        amount: Arc<Amount>,
+        secret: Arc<Secret>,
+        c: Arc<PublicKey>,
+        id: Option<String>,
+    ) -> Self {
         Self {
             inner: ProofSdk {
                 amount: *amount.as_ref().deref(),
-                secret,
+                secret: secret.as_ref().deref().clone(),
                 c: c.as_ref().deref().clone(),
                 id,
             },
@@ -31,8 +36,8 @@ impl Proof {
         Arc::new(self.inner.amount.into())
     }
 
-    pub fn secret(&self) -> String {
-        self.inner.secret.clone()
+    pub fn secret(&self) -> Arc<Secret> {
+        Arc::new(self.inner.secret.clone().into())
     }
 
     pub fn c(&self) -> Arc<PublicKey> {
@@ -48,7 +53,7 @@ impl From<&Proof> for ProofSdk {
     fn from(proof: &Proof) -> ProofSdk {
         ProofSdk {
             amount: *proof.amount().as_ref().deref(),
-            secret: proof.secret(),
+            secret: proof.secret().as_ref().deref().clone(),
             c: proof.c().deref().into(),
             id: proof.id(),
         }
@@ -67,6 +72,7 @@ pub mod mint {
 
     use cashu::nuts::nut00::mint::Proof as ProofSdk;
 
+    use crate::types::Secret;
     use crate::Amount;
     use crate::PublicKey;
 
@@ -84,14 +90,14 @@ pub mod mint {
     impl Proof {
         pub fn new(
             amount: Option<Arc<Amount>>,
-            secret: String,
+            secret: Arc<Secret>,
             c: Option<Arc<PublicKey>>,
             id: Option<String>,
         ) -> Self {
             Self {
                 inner: ProofSdk {
                     amount: amount.map(|a| *a.as_ref().deref()),
-                    secret,
+                    secret: secret.as_ref().deref().clone(),
                     c: c.map(|c| c.as_ref().into()),
                     id,
                 },
@@ -102,8 +108,8 @@ pub mod mint {
             self.inner.amount.map(|a| Arc::new(a.into()))
         }
 
-        pub fn secret(&self) -> String {
-            self.inner.secret.clone()
+        pub fn secret(&self) -> Arc<Secret> {
+            Arc::new(self.inner.secret.clone().into())
         }
 
         pub fn c(&self) -> Option<Arc<PublicKey>> {
diff --git a/bindings/cashu-ffi/src/types/mod.rs b/bindings/cashu-ffi/src/types/mod.rs
index 03a97470..27a825a3 100644
--- a/bindings/cashu-ffi/src/types/mod.rs
+++ b/bindings/cashu-ffi/src/types/mod.rs
@@ -1,4 +1,6 @@
 pub mod amount;
 pub mod bolt11_invoice;
+pub mod secret;
 
 pub use bolt11_invoice::Bolt11Invoice;
+pub use secret::Secret;
diff --git a/bindings/cashu-ffi/src/types/secret.rs b/bindings/cashu-ffi/src/types/secret.rs
new file mode 100644
index 00000000..788028db
--- /dev/null
+++ b/bindings/cashu-ffi/src/types/secret.rs
@@ -0,0 +1,38 @@
+use std::ops::Deref;
+
+use cashu::secret::Secret as SecretSdk;
+
+pub struct Secret {
+    inner: SecretSdk,
+}
+
+impl Deref for Secret {
+    type Target = SecretSdk;
+    fn deref(&self) -> &Self::Target {
+        &self.inner
+    }
+}
+
+impl Secret {
+    pub fn new() -> Self {
+        Self {
+            inner: SecretSdk::new(),
+        }
+    }
+
+    pub fn as_bytes(&self) -> Vec<u8> {
+        self.inner.as_bytes().to_vec()
+    }
+}
+
+impl From<SecretSdk> for Secret {
+    fn from(inner: SecretSdk) -> Secret {
+        Secret { inner }
+    }
+}
+
+impl From<Secret> for SecretSdk {
+    fn from(secret: Secret) -> SecretSdk {
+        secret.inner
+    }
+}