From ab761f417b214689f5c0b3fb21e7a84b642c4aff Mon Sep 17 00:00:00 2001
From: Constance Beguier <constance@qed-it.com>
Date: Tue, 28 Apr 2026 09:00:39 +0200
Subject: [PATCH 1/4] Create type aliases EnCiphertext and CompactEncCiphertext

---
 src/bundle.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/bundle.rs b/src/bundle.rs
index d7ba7e0f..45a7bb72 100644
--- a/src/bundle.rs
+++ b/src/bundle.rs
@@ -420,6 +420,9 @@ impl<Proof: DynamicUsage> DynamicUsage for OutputDescription<Proof> {
     }
 }
 
+type EncCiphertext = NoteBytesData<{ ENC_CIPHERTEXT_SIZE }>;
+type CompactEncCiphertext = NoteBytesData<{ COMPACT_NOTE_SIZE }>;
+
 impl<A> ShieldedOutput<SaplingDomain> for OutputDescription<A> {
     fn ephemeral_key(&self) -> EphemeralKeyBytes {
         self.ephemeral_key.clone()
@@ -433,11 +436,11 @@ impl<A> ShieldedOutput<SaplingDomain> for OutputDescription<A> {
         self.cmu.to_bytes()
     }
 
-    fn enc_ciphertext(&self) -> Option<&NoteBytesData<{ ENC_CIPHERTEXT_SIZE }>> {
+    fn enc_ciphertext(&self) -> Option<&EncCiphertext> {
         Some(&self.enc_ciphertext)
     }
 
-    fn enc_ciphertext_compact(&self) -> NoteBytesData<{ COMPACT_NOTE_SIZE }> {
+    fn enc_ciphertext_compact(&self) -> CompactEncCiphertext {
         unimplemented!("This function is not required for sapling")
     }
 }

From 044e7e8b42c1292527a0a56c2b94d53290f2be25 Mon Sep 17 00:00:00 2001
From: Constance Beguier <constance@qed-it.com>
Date: Tue, 28 Apr 2026 09:11:09 +0200
Subject: [PATCH 2/4] Implement enc_ciphertext_compact for OutputDescription

---
 src/bundle.rs | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/bundle.rs b/src/bundle.rs
index 45a7bb72..d792afb3 100644
--- a/src/bundle.rs
+++ b/src/bundle.rs
@@ -441,7 +441,9 @@ impl<A> ShieldedOutput<SaplingDomain> for OutputDescription<A> {
     }
 
     fn enc_ciphertext_compact(&self) -> CompactEncCiphertext {
-        unimplemented!("This function is not required for sapling")
+        let mut data = [0u8; COMPACT_NOTE_SIZE];
+        data.copy_from_slice(&self.enc_ciphertext.as_ref()[..COMPACT_NOTE_SIZE]);
+        NoteBytesData(data)
     }
 }
 
@@ -501,12 +503,12 @@ impl OutputDescriptionV5 {
 
 impl<A> From<OutputDescription<A>> for CompactOutputDescription {
     fn from(out: OutputDescription<A>) -> CompactOutputDescription {
+        let enc_ciphertext = out.enc_ciphertext_compact().0;
+
         CompactOutputDescription {
             ephemeral_key: out.ephemeral_key,
             cmu: out.cmu,
-            enc_ciphertext: out.enc_ciphertext.as_ref()[..COMPACT_NOTE_SIZE]
-                .try_into()
-                .unwrap(),
+            enc_ciphertext,
         }
     }
 }

From 2e3b4e816e3acf0bc5904d1ecd994572a1887914 Mon Sep 17 00:00:00 2001
From: Constance Beguier <constance@qed-it.com>
Date: Tue, 28 Apr 2026 09:34:33 +0200
Subject: [PATCH 3/4] Move type aliases

---
 src/bundle.rs          | 5 +----
 src/note_encryption.rs | 7 +++++--
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/bundle.rs b/src/bundle.rs
index d792afb3..5f15c9e7 100644
--- a/src/bundle.rs
+++ b/src/bundle.rs
@@ -13,7 +13,7 @@ use crate::{
     constants::GROTH_PROOF_SIZE,
     note::ExtractedNoteCommitment,
     note_encryption::{
-        CompactOutputDescription, SaplingDomain, COMPACT_NOTE_SIZE, ENC_CIPHERTEXT_SIZE,
+        CompactOutputDescription, SaplingDomain, COMPACT_NOTE_SIZE, ENC_CIPHERTEXT_SIZE,EncCiphertext, CompactEncCiphertext
     },
     value::ValueCommitment,
     Nullifier,
@@ -420,9 +420,6 @@ impl<Proof: DynamicUsage> DynamicUsage for OutputDescription<Proof> {
     }
 }
 
-type EncCiphertext = NoteBytesData<{ ENC_CIPHERTEXT_SIZE }>;
-type CompactEncCiphertext = NoteBytesData<{ COMPACT_NOTE_SIZE }>;
-
 impl<A> ShieldedOutput<SaplingDomain> for OutputDescription<A> {
     fn ephemeral_key(&self) -> EphemeralKeyBytes {
         self.ephemeral_key.clone()
diff --git a/src/note_encryption.rs b/src/note_encryption.rs
index 5305b49d..cd18a9f7 100644
--- a/src/note_encryption.rs
+++ b/src/note_encryption.rs
@@ -140,6 +140,9 @@ impl SaplingDomain {
     }
 }
 
+pub(crate) type EncCiphertext = NoteBytesData<{ ENC_CIPHERTEXT_SIZE }>;
+pub(crate) type CompactEncCiphertext = NoteBytesData<{ COMPACT_NOTE_SIZE }>;
+
 impl Domain for SaplingDomain {
     type EphemeralSecretKey = EphemeralSecretKey;
     // It is acceptable for this to be a point rather than a byte array, because we
@@ -160,9 +163,9 @@ impl Domain for SaplingDomain {
     type Memo = [u8; MEMO_SIZE];
 
     type NotePlaintextBytes = NoteBytesData<{ NOTE_PLAINTEXT_SIZE }>;
-    type NoteCiphertextBytes = NoteBytesData<{ ENC_CIPHERTEXT_SIZE }>;
+    type NoteCiphertextBytes = EncCiphertext;
     type CompactNotePlaintextBytes = NoteBytesData<{ COMPACT_NOTE_SIZE }>;
-    type CompactNoteCiphertextBytes = NoteBytesData<{ COMPACT_NOTE_SIZE }>;
+    type CompactNoteCiphertextBytes = CompactEncCiphertext;
 
     fn derive_esk(note: &Self::Note) -> Option<Self::EphemeralSecretKey> {
         note.derive_esk()

From 5ec76a1dea5bd471d86ea4eb021a079fda82dd05 Mon Sep 17 00:00:00 2001
From: Constance Beguier <constance@qed-it.com>
Date: Tue, 28 Apr 2026 11:27:42 +0200
Subject: [PATCH 4/4] rustfmt

---
 src/bundle.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/bundle.rs b/src/bundle.rs
index 5f15c9e7..035c32d2 100644
--- a/src/bundle.rs
+++ b/src/bundle.rs
@@ -13,7 +13,8 @@ use crate::{
     constants::GROTH_PROOF_SIZE,
     note::ExtractedNoteCommitment,
     note_encryption::{
-        CompactOutputDescription, SaplingDomain, COMPACT_NOTE_SIZE, ENC_CIPHERTEXT_SIZE,EncCiphertext, CompactEncCiphertext
+        CompactEncCiphertext, CompactOutputDescription, EncCiphertext, SaplingDomain,
+        COMPACT_NOTE_SIZE, ENC_CIPHERTEXT_SIZE,
     },
     value::ValueCommitment,
     Nullifier,