diff --git a/iris-mpc-common/Cargo.toml b/iris-mpc-common/Cargo.toml
index 3be0d57ec..383cda00a 100644
--- a/iris-mpc-common/Cargo.toml
+++ b/iris-mpc-common/Cargo.toml
@@ -5,37 +5,37 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-aws-config.workspace = true
-aws-sdk-kms.workspace = true
-aws-sdk-sns.workspace = true
-aws-sdk-s3.workspace = true
-aws-sdk-secretsmanager.workspace = true
-clap.workspace = true
-rand.workspace = true
-bytemuck.workspace = true
-eyre.workspace = true
+aws-config = { version = "1.5.4", features = ["behavior-version-latest"] }
+aws-sdk-kms = { version = "1.37.0" }
+aws-sdk-sns = { version = "1.37.0" }
+aws-sdk-s3 = { version = "1.42.0" }
+aws-sdk-secretsmanager = { version = "1.41.0" }
+clap = { version = "4", features = ["derive", "env"] }
+rand = "0.8"
+bytemuck = "1.17"
+eyre = "0.6"
 thiserror = "1"
-rayon.workspace = true
-itertools.workspace = true
-base64.workspace = true
-serde.workspace = true
-serde_json.workspace = true
+rayon = "1.5.1"
+itertools = "0.13"
+base64 = "0.22.1"
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1"
 config = "0.14.0"
-tokio.workspace = true
-tracing.workspace = true
-tracing-subscriber.workspace = true
+tokio = { version = "1.39", features = ["full", "rt-multi-thread"] }
+tracing = "0.1.40"
+tracing-subscriber = { version = "0.3.15", features = ["env-filter"] }
 
-reqwest = { workspace = true, features = ["blocking", "json"] }
+reqwest = { version = "0.12", features = ["blocking", "json"] }
 sodiumoxide = "0.2.7"
 hmac = "0.12"
 http = "1.1.0"
 opentelemetry = "0.21.0"
-telemetry-batteries.workspace = true
+telemetry-batteries = { git = "https://github.com/worldcoin/telemetry-batteries.git", rev = "802a4f39f358e077b11c8429b4c65f3e45b85959" }
 percent-encoding = "2"
 sha2 = "0.10"
 time = { version = "^0.3.6", features = ["formatting", "macros"] }
 url = "2"
-hex.workspace = true
+hex = "0.4.3"
 zeroize = "1.8.1"
 wiremock = "0.6.1"
 digest = "0.10.7"
diff --git a/iris-mpc-common/src/galois_engine.rs b/iris-mpc-common/src/galois_engine.rs
index c76b03d2e..7e75f33ef 100644
--- a/iris-mpc-common/src/galois_engine.rs
+++ b/iris-mpc-common/src/galois_engine.rs
@@ -238,10 +238,13 @@ pub mod degree4 {
     };
     use base64::{prelude::BASE64_STANDARD, Engine};
     use rand::{CryptoRng, Rng};
+    use serde::{Deserialize, Serialize};
+    use serde_big_array::BigArray;
 
-    #[derive(Debug, Clone, PartialEq, Eq, Hash)]
+    #[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
     pub struct GaloisRingIrisCodeShare {
         pub id:    usize,
+        #[serde(with = "BigArray")]
         pub coefs: [u16; IRIS_CODE_LENGTH],
     }
 
@@ -457,13 +460,13 @@ pub mod degree4 {
         }
 
         pub fn to_base64(&self) -> String {
-            BASE64_STANDARD.encode(bytemuck::cast_slice(&self.coefs))
+            let as_vec_u8 = bincode::serialize(&self).expect("to serialize");
+            BASE64_STANDARD.encode::<Vec<u8>>(as_vec_u8)
         }
 
-        pub fn from_base64(id: usize, s: &str) -> eyre::Result<Self> {
-            let mut coefs = [0u16; IRIS_CODE_LENGTH];
-            BASE64_STANDARD.decode_slice(s, bytemuck::cast_slice_mut(&mut coefs))?;
-            Ok(Self::new(id, coefs))
+        pub fn from_base64(s: &str) -> eyre::Result<Self> {
+            let decoded_bytes = BASE64_STANDARD.decode(s)?;
+            Ok(bincode::deserialize(&decoded_bytes)?)
         }
     }
 
@@ -598,7 +601,7 @@ pub mod degree4 {
             let shares = GaloisRingIrisCodeShare::encode_mask_code(&code, &mut rng);
             for i in 0..3 {
                 let s = shares[i].to_base64();
-                let decoded = GaloisRingIrisCodeShare::from_base64(i + 1, &s).unwrap();
+                let decoded = GaloisRingIrisCodeShare::from_base64(&s).unwrap();
                 assert_eq!(shares[i].coefs, decoded.coefs);
             }
         }
diff --git a/iris-mpc/src/bin/server.rs b/iris-mpc/src/bin/server.rs
index 6984603ed..402c82cab 100644
--- a/iris-mpc/src/bin/server.rs
+++ b/iris-mpc/src/bin/server.rs
@@ -63,7 +63,6 @@ static CURRENT_BATCH_SIZE: LazyLock<Mutex<usize>> = LazyLock::new(|| Mutex::new(
 
 #[allow(clippy::type_complexity)]
 fn preprocess_iris_message_shares(
-    party_id: usize,
     code_shares: String,
     mask_shares: String,
 ) -> eyre::Result<(
@@ -74,9 +73,9 @@ fn preprocess_iris_message_shares(
     Vec<GaloisRingIrisCodeShare>,
     Vec<GaloisRingIrisCodeShare>,
 )> {
-    let mut iris_share = GaloisRingIrisCodeShare::from_base64(party_id + 1, &code_shares)
+    let mut iris_share = GaloisRingIrisCodeShare::from_base64(&code_shares)
         .context("Failed to base64 parse iris code")?;
-    let mut mask_share = GaloisRingIrisCodeShare::from_base64(party_id + 1, &mask_shares)
+    let mut mask_share = GaloisRingIrisCodeShare::from_base64(&mask_shares)
         .context("Failed to base64 parse iris mask")?;
 
     // Original for storage.
@@ -204,7 +203,6 @@ async fn receive_batch(
                 // Preprocess shares for left eye.
                 let left_future = spawn_blocking(move || {
                     preprocess_iris_message_shares(
-                        party_id,
                         iris_message_share.left_iris_code_shares,
                         iris_message_share.left_iris_mask_shares,
                     )
@@ -213,7 +211,6 @@ async fn receive_batch(
                 // Preprocess shares for right eye.
                 let right_future = spawn_blocking(move || {
                     preprocess_iris_message_shares(
-                        party_id,
                         iris_message_share.right_iris_code_shares,
                         iris_message_share.right_iris_mask_shares,
                     )