diff --git a/src/issuance.rs b/src/issuance.rs
index 3316cfe8..b36c2350 100644
--- a/src/issuance.rs
+++ b/src/issuance.rs
@@ -2,7 +2,7 @@
 
 use memuse::DynamicUsage;
 use nonempty::NonEmpty;
-use rand::RngCore;
+use rand::{CryptoRng, RngCore};
 use std::fmt;
 
 use crate::keys::IssuerValidatingKey;
@@ -28,6 +28,17 @@ impl IssueAction<Unauthorized> {
             authorization: Unauthorized,
         }
     }
+
+    /// inject the `sighash` for signature into the bundle.
+    pub fn prepare(self, sighash: [u8; 32]) -> IssueAction<Prepared> {
+        return IssueAction {
+            ik: self.ik,
+            asset_desc: self.asset_desc,
+            notes: self.notes,
+            finalize: self.finalize,
+            authorization: Prepared { sighash },
+        };
+    }
 }
 
 impl<T: IssueAuth> IssueAction<T> {
@@ -234,7 +245,6 @@ impl Default for IssueBundle<Unauthorized> {
 }
 
 impl<T: IssueAuth> IssueBundle<T> {
-
     /// Return the actions for a given `IssueBundle`.
     pub fn actions(&self) -> &Vec<IssueAction<T>> {
         &self.actions
@@ -342,6 +352,22 @@ impl IssueBundle<Unauthorized> {
 
         Ok(())
     }
+
+    /// Loads the sighash into this bundle, preparing it for signing.
+    ///
+    /// This API ensures that all signatures are created over the same sighash.
+    /// pub fn prepare<R: RngCore + CryptoRng>(
+    //         self,
+    //         mut rng: R,
+    pub fn prepare(self, sighash: [u8; 32]) -> IssueBundle<Prepared> {
+        IssueBundle {
+            actions: self
+                .actions
+                .into_iter()
+                .map(|a| a.prepare(sighash))
+                .collect(),
+        }
+    }
 }
 
 /// Errors produced during the issuance process
@@ -505,6 +531,39 @@ mod tests {
             IssueActionAlreadyFinalized
         );
     }
+
+    #[test]
+    fn issue_bundle_prepare() {
+        let mut rng = OsRng;
+        let sk = SpendingKey::random(&mut rng);
+        let isk: IssuerAuthorizingKey = (&sk).into();
+        let ik: IssuerValidatingKey = (&isk).into();
+
+        let fvk = FullViewingKey::from(&sk);
+        let recipient = fvk.address_at(0u32, Scope::External);
+
+        let mut bundle = IssueBundle::new();
+
+        bundle
+            .add_recipient(
+                ik.clone(),
+                String::from("Frost"),
+                recipient,
+                NoteValue::from_raw(5),
+                false,
+                rng,
+            )
+            .unwrap();
+
+        let fake_sighash = [1; 32];
+        let prepared = bundle.prepare(fake_sighash);
+
+        let action = prepared
+            .get_action(ik.clone(), String::from("Frost"))
+            .unwrap();
+        let auth = action.authorization();
+        assert_eq!(auth.sighash, fake_sighash);
+    }
 }
 
 // mod tests {
diff --git a/src/keys.rs b/src/keys.rs
index 37a7b0ea..0e495207 100644
--- a/src/keys.rs
+++ b/src/keys.rs
@@ -212,7 +212,11 @@ impl IssuerAuthorizingKey {
     /// RXXXX
     ///
     /// XXXXX
-    pub fn sign(&self, rng: &mut (impl RngCore + CryptoRng), msg: &[u8]) -> redpallas::Signature<SpendAuth> {
+    pub fn sign(
+        &self,
+        rng: &mut (impl RngCore + CryptoRng),
+        msg: &[u8],
+    ) -> redpallas::Signature<SpendAuth> {
         self.0.sign(rng, msg)
     }
 }
diff --git a/src/note/note_type.rs b/src/note/note_type.rs
index 3571b215..c3f2480a 100644
--- a/src/note/note_type.rs
+++ b/src/note/note_type.rs
@@ -92,17 +92,13 @@ pub mod testing {
         pub fn arb_note_type()(
             is_native in prop::bool::ANY,
             sk in arb_spending_key(),
-            // bytes32a in prop::array::uniform32(prop::num::u8::ANY),
-            // bytes32b in prop::array::uniform32(prop::num::u8::ANY),
-            vec in prop::collection::vec(any::<u8>(), 0..=255),
+            str in "[A-Za-z]{255}",
         ) -> NoteType {
             if is_native {
                 NoteType::native()
             } else {
-                //let bytes64 = [bytes32a, bytes32b].concat();
-                let asset_desc = String::from_utf8(vec).unwrap();
                 let isk = IssuerAuthorizingKey::from(&sk);
-                NoteType::derive(&IssuerValidatingKey::from(&isk), asset_desc.as_str())
+                NoteType::derive(&IssuerValidatingKey::from(&isk), &str)
             }
         }
     }