diff --git a/crates/model/src/bytes_hex.rs b/crates/model/src/bytes_hex.rs
new file mode 100644
index 0000000000..4dffe2d5f0
--- /dev/null
+++ b/crates/model/src/bytes_hex.rs
@@ -0,0 +1,51 @@
+//! Serialization of Vec<u8> to 0x prefixed hex string
+
+use serde::{de::Error, Deserialize, Deserializer, Serializer};
+use std::borrow::Cow;
+
+pub fn serialize<S, T>(bytes: T, serializer: S) -> Result<S::Ok, S::Error>
+where
+    S: Serializer,
+    T: AsRef<[u8]>,
+{
+    let mut v = vec![0u8; 2 + bytes.as_ref().len() * 2];
+    v[0] = b'0';
+    v[1] = b'x';
+    // Unwrap because only possible error is vector wrong size which cannot happen.
+    hex::encode_to_slice(bytes, &mut v[2..]).unwrap();
+    // Unwrap because encoded data is always valid utf8.
+    serializer.serialize_str(&String::from_utf8(v).unwrap())
+}
+
+pub fn deserialize<'de, D>(deserializer: D) -> Result<Vec<u8>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let prefixed_hex_str = Cow::<str>::deserialize(deserializer)?;
+    let hex_str = prefixed_hex_str
+        .strip_prefix("0x")
+        .ok_or_else(|| D::Error::custom("missing '0x' prefix"))?;
+    hex::decode(hex_str).map_err(D::Error::custom)
+}
+
+#[cfg(test)]
+mod tests {
+
+    #[derive(Debug, serde::Deserialize, serde::Serialize, Eq, PartialEq)]
+    struct S {
+        #[serde(with = "super")]
+        b: Vec<u8>,
+    }
+
+    #[test]
+    fn json() {
+        let orig = S { b: vec![0, 1] };
+        let serialized = serde_json::to_value(&orig).unwrap();
+        let expected = serde_json::json!({
+            "b": "0x0001"
+        });
+        assert_eq!(serialized, expected);
+        let deserialized: S = serde_json::from_value(expected).unwrap();
+        assert_eq!(orig, deserialized);
+    }
+}
diff --git a/crates/model/src/lib.rs b/crates/model/src/lib.rs
index d13116cf37..132f3d7fa1 100644
--- a/crates/model/src/lib.rs
+++ b/crates/model/src/lib.rs
@@ -2,6 +2,7 @@
 
 pub mod app_id;
 pub mod auction;
+pub mod bytes_hex;
 pub mod order;
 pub mod ratio_as_decimal;
 pub mod signature;
diff --git a/crates/shared/src/balancer_sor_api.rs b/crates/shared/src/balancer_sor_api.rs
index b00b748c60..2dd2274b4d 100644
--- a/crates/shared/src/balancer_sor_api.rs
+++ b/crates/shared/src/balancer_sor_api.rs
@@ -10,7 +10,6 @@ use model::u256_decimal;
 use num::BigInt;
 use reqwest::{Client, IntoUrl, Url};
 use serde::{Deserialize, Serialize};
-use web3::types::Bytes;
 
 /// Trait for mockable Balancer SOR API.
 #[mockall::automock]
@@ -149,7 +148,8 @@ pub struct Swap {
     #[serde(with = "u256_decimal")]
     pub amount: U256,
     /// Additional user data to pass to the pool.
-    pub user_data: Bytes,
+    #[serde(with = "model::bytes_hex")]
+    pub user_data: Vec<u8>,
 }
 
 impl Quote {
diff --git a/crates/shared/src/lib.rs b/crates/shared/src/lib.rs
index 77d1e270b5..4168a72e45 100644
--- a/crates/shared/src/lib.rs
+++ b/crates/shared/src/lib.rs
@@ -41,7 +41,6 @@ use std::{
     future::Future,
     time::{Duration, Instant},
 };
-use web3::types::Bytes;
 
 pub type Web3Transport = DynTransport;
 pub type Web3 = DynWeb3;
@@ -66,10 +65,10 @@ pub async fn measure_time<T>(future: impl Future<Output = T>, timer: impl FnOnce
 }
 
 pub fn debug_bytes(
-    bytes: &Bytes,
+    bytes: impl AsRef<[u8]>,
     formatter: &mut std::fmt::Formatter,
 ) -> Result<(), std::fmt::Error> {
-    formatter.write_fmt(format_args!("0x{}", hex::encode(&bytes.0)))
+    formatter.write_fmt(format_args!("0x{}", hex::encode(bytes.as_ref())))
 }
 
 /// anyhow errors are not clonable natively. This is a workaround that creates a new anyhow error
diff --git a/crates/shared/src/oneinch_api.rs b/crates/shared/src/oneinch_api.rs
index 6fe8eb5d99..7a2ddab384 100644
--- a/crates/shared/src/oneinch_api.rs
+++ b/crates/shared/src/oneinch_api.rs
@@ -4,7 +4,7 @@
 //! <https://docs.1inch.io/docs/aggregation-protocol/api/swagger>
 //! Although there is no documentation about API v4.1, it exists and is identical to v4.0 except it
 //! uses EIP 1559 gas prices.
-use crate::solver_utils::{deserialize_prefixed_hex, Slippage};
+use crate::solver_utils::Slippage;
 use anyhow::{ensure, Context, Result};
 use cached::{Cached, TimedCache};
 use ethcontract::{H160, U256};
@@ -360,7 +360,7 @@ pub struct ProtocolRouteSegment {
 pub struct Transaction {
     pub from: H160,
     pub to: H160,
-    #[serde(deserialize_with = "deserialize_prefixed_hex")]
+    #[serde(with = "model::bytes_hex")]
     pub data: Vec<u8>,
     #[serde(with = "u256_decimal")]
     pub value: U256,
diff --git a/crates/shared/src/paraswap_api.rs b/crates/shared/src/paraswap_api.rs
index 742e898f5e..396f0053d8 100644
--- a/crates/shared/src/paraswap_api.rs
+++ b/crates/shared/src/paraswap_api.rs
@@ -10,7 +10,6 @@ use serde::{
 };
 use serde_json::Value;
 use thiserror::Error;
-use web3::types::Bytes;
 
 const BASE_URL: &str = "https://apiv5.paraswap.io";
 
@@ -325,7 +324,8 @@ pub struct TransactionBuilderResponse {
     pub value: U256,
     /// the calldata for the transaction
     #[derivative(Debug(format_with = "debug_bytes"))]
-    pub data: Bytes,
+    #[serde(with = "model::bytes_hex")]
+    pub data: Vec<u8>,
     /// the suggested gas price
     #[serde(with = "u256_decimal")]
     pub gas_price: U256,
diff --git a/crates/shared/src/solver_utils.rs b/crates/shared/src/solver_utils.rs
index 7e8e4f9dd2..b8799d2be7 100644
--- a/crates/shared/src/solver_utils.rs
+++ b/crates/shared/src/solver_utils.rs
@@ -49,14 +49,3 @@ where
     let decimal_str = Cow::<str>::deserialize(deserializer)?;
     decimal_str.parse::<f64>().map_err(D::Error::custom)
 }
-
-pub fn deserialize_prefixed_hex<'de, D>(deserializer: D) -> Result<Vec<u8>, D::Error>
-where
-    D: Deserializer<'de>,
-{
-    let prefixed_hex_str = Cow::<str>::deserialize(deserializer)?;
-    let hex_str = prefixed_hex_str
-        .strip_prefix("0x")
-        .ok_or_else(|| D::Error::custom("hex missing '0x' prefix"))?;
-    hex::decode(hex_str).map_err(D::Error::custom)
-}
diff --git a/crates/shared/src/univ3_router_api.rs b/crates/shared/src/univ3_router_api.rs
index d698bb4c88..58ff3ff352 100644
--- a/crates/shared/src/univ3_router_api.rs
+++ b/crates/shared/src/univ3_router_api.rs
@@ -1,6 +1,5 @@
 //! Bindings for an instance of https://github.com/cowprotocol/univ3-api .
 
-use crate::solver_utils::deserialize_prefixed_hex;
 use anyhow::{Context, Result};
 use model::u256_decimal;
 use primitive_types::{H160, U256};
@@ -32,7 +31,7 @@ pub struct Response {
     pub quote: U256,
     #[serde(with = "serde_with::rust::display_fromstr")]
     pub gas: u64,
-    #[serde(deserialize_with = "deserialize_prefixed_hex")]
+    #[serde(with = "model::bytes_hex")]
     pub call_data: Vec<u8>,
 }
 
diff --git a/crates/shared/src/zeroex_api.rs b/crates/shared/src/zeroex_api.rs
index 0156e3b0e3..8256ce90ac 100644
--- a/crates/shared/src/zeroex_api.rs
+++ b/crates/shared/src/zeroex_api.rs
@@ -15,7 +15,6 @@ use reqwest::{Client, IntoUrl, Url};
 use serde::Deserialize;
 use std::collections::HashSet;
 use thiserror::Error;
-use web3::types::Bytes;
 
 const ORDERS_MAX_PAGE_SIZE: usize = 1_000;
 
@@ -137,7 +136,8 @@ impl Default for OrdersQuery {
 pub struct OrderMetadata {
     #[derivative(Default(value = "chrono::MIN_DATETIME"))]
     pub created_at: DateTime<Utc>,
-    pub order_hash: Bytes,
+    #[serde(with = "model::bytes_hex")]
+    pub order_hash: Vec<u8>,
     #[serde(with = "serde_with::rust::display_fromstr")]
     pub remaining_fillable_taker_amount: u128,
 }
@@ -261,7 +261,8 @@ pub struct SwapResponse {
     pub price: PriceResponse,
     pub to: H160,
     #[derivative(Debug(format_with = "debug_bytes"))]
-    pub data: Bytes,
+    #[serde(with = "model::bytes_hex")]
+    pub data: Vec<u8>,
     #[serde(with = "u256_decimal")]
     pub value: U256,
 }
@@ -587,11 +588,10 @@ mod tests {
                 per_page: 1000,
                 records: vec![OrderRecord {
                     metadata: OrderMetadata {
-                        order_hash: Bytes(
+                        order_hash:
                             hex::decode(
                                 "003427369d4c2a6b0aceeb7b315bb9a6086bc6fc4c887aa51efc73b662c9d127"
-                            ).unwrap()
-                        ),
+                            ).unwrap(),
                         remaining_fillable_taker_amount: 262467000000000000u128,
                         created_at: Utc.ymd(2022, 2, 26).and_hms_milli(6, 59, 0, 440)
                     },
@@ -646,9 +646,9 @@ mod tests {
                         estimated_gas: 111000,
                     },
                     to: crate::addr!("def1c0ded9bec7f1a1670819833240f027b25eff"),
-                    data: Bytes(hex::decode(
+                    data: hex::decode(
                         "d9627aa40000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000016345785d8a00000000000000000000000000000000000000000000000000001206e6c0056936e100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002000000000000000000000000c02aaa39b223fe8d0a0e5c4f27ead9083c756cc20000000000000000000000006810e776880c02933d47db1b9fc05908e5386b96869584cd0000000000000000000000001000000000000000000000000000000000000011000000000000000000000000000000000000000000000092415e982f60d431ba"
-                    ).unwrap()),
+                    ).unwrap(),
                     value: U256::from_dec_str("0").unwrap(),
                 }
             );
diff --git a/crates/solver/src/liquidity/zeroex.rs b/crates/solver/src/liquidity/zeroex.rs
index 86fb8aedcc..2187cd19b3 100644
--- a/crates/solver/src/liquidity/zeroex.rs
+++ b/crates/solver/src/liquidity/zeroex.rs
@@ -63,7 +63,7 @@ impl ZeroExLiquidity {
         }
 
         let limit_order = LimitOrder {
-            id: hex::encode(&record.metadata.order_hash.0),
+            id: hex::encode(&record.metadata.order_hash),
             sell_token: record.order.maker_token,
             buy_token: record.order.taker_token,
             sell_amount,
diff --git a/crates/solver/src/settlement_access_list.rs b/crates/solver/src/settlement_access_list.rs
index 6c5e74b885..19d8e11df8 100644
--- a/crates/solver/src/settlement_access_list.rs
+++ b/crates/solver/src/settlement_access_list.rs
@@ -157,6 +157,7 @@ impl AccessListEstimating for TenderlyAccessList {
     ) -> Result<Vec<Result<AccessList>>> {
         Ok(futures::future::join_all(txs.iter().map(|tx| async {
             let (from, to, input) = resolve_call_request(tx)?;
+            let input = input.0;
             let block_number = self.tenderly.block_number(&self.network_id).await?;
 
             let request = TenderlyRequest {
diff --git a/crates/solver/src/settlement_simulation.rs b/crates/solver/src/settlement_simulation.rs
index 939a9cab1a..44c5cbf476 100644
--- a/crates/solver/src/settlement_simulation.rs
+++ b/crates/solver/src/settlement_simulation.rs
@@ -18,7 +18,7 @@ use reqwest::{
 };
 use serde::{de::DeserializeOwned, Deserialize, Serialize};
 use shared::Web3;
-use web3::types::{AccessList, BlockId, Bytes};
+use web3::types::{AccessList, BlockId};
 
 const SIMULATE_BATCH_SIZE: usize = 10;
 
@@ -169,7 +169,7 @@ pub async fn simulate_before_after_access_list(
         network_id,
         block_number,
         from,
-        input: transaction.input,
+        input: transaction.input.0,
         to,
         generate_access_list: false,
         transaction_index: Some(transaction_index),
@@ -248,7 +248,8 @@ pub struct TenderlyRequest {
     pub network_id: String,
     pub block_number: u64,
     pub from: Address,
-    pub input: Bytes,
+    #[serde(with = "model::bytes_hex")]
+    pub input: Vec<u8>,
     pub to: Address,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub transaction_index: Option<u64>,
diff --git a/crates/solver/src/solver/balancer_sor_solver.rs b/crates/solver/src/solver/balancer_sor_solver.rs
index 50bf2ea5e7..93982c8705 100644
--- a/crates/solver/src/solver/balancer_sor_solver.rs
+++ b/crates/solver/src/solver/balancer_sor_solver.rs
@@ -193,7 +193,7 @@ impl Interaction for BatchSwap {
                     swap.asset_in_index.into(),
                     swap.asset_out_index.into(),
                     swap.amount,
-                    Bytes(swap.user_data.0.clone()),
+                    Bytes(swap.user_data.clone()),
                 )
             })
             .collect();
diff --git a/crates/solver/src/solver/paraswap_solver.rs b/crates/solver/src/solver/paraswap_solver.rs
index 64f5ddb0a2..9ea5c87565 100644
--- a/crates/solver/src/solver/paraswap_solver.rs
+++ b/crates/solver/src/solver/paraswap_solver.rs
@@ -196,7 +196,7 @@ fn decimals(token_info: &HashMap<H160, TokenInfo>, token: &H160) -> Result<usize
 
 impl Interaction for TransactionBuilderResponse {
     fn encode(&self) -> Vec<EncodedInteraction> {
-        vec![(self.to, self.value, Bytes(self.data.0.clone()))]
+        vec![(self.to, self.value, Bytes(self.data.clone()))]
     }
 }
 
diff --git a/crates/solver/src/solver/zeroex_solver.rs b/crates/solver/src/solver/zeroex_solver.rs
index e3a0dac010..1541c99e2b 100644
--- a/crates/solver/src/solver/zeroex_solver.rs
+++ b/crates/solver/src/solver/zeroex_solver.rs
@@ -143,7 +143,7 @@ impl From<ZeroExResponseError> for SettlementError {
 
 impl Interaction for SwapResponse {
     fn encode(&self) -> Vec<EncodedInteraction> {
-        vec![(self.to, self.value, Bytes(self.data.0.clone()))]
+        vec![(self.to, self.value, Bytes(self.data.clone()))]
     }
 }
 
@@ -269,7 +269,7 @@ mod tests {
                     estimated_gas: Default::default(),
                 },
                 to: shared::addr!("0000000000000000000000000000000000000000"),
-                data: web3::types::Bytes(hex::decode("00").unwrap()),
+                data: hex::decode("00").unwrap(),
                 value: U256::from_dec_str("0").unwrap(),
             })
         });
@@ -407,7 +407,7 @@ mod tests {
                     estimated_gas: Default::default(),
                 },
                 to: shared::addr!("0000000000000000000000000000000000000000"),
-                data: web3::types::Bytes(hex::decode("").unwrap()),
+                data: hex::decode("").unwrap(),
                 value: U256::from_dec_str("0").unwrap(),
             })
         });
@@ -483,7 +483,7 @@ mod tests {
                     estimated_gas: Default::default(),
                 },
                 to: shared::addr!("0000000000000000000000000000000000000000"),
-                data: web3::types::Bytes(vec![]),
+                data: vec![],
                 value: 0.into(),
             })
         });