diff --git a/blockchain/chain_sync/src/sync.rs b/blockchain/chain_sync/src/sync.rs
index 30ffcaeee4f6..c18b0c811bd8 100644
--- a/blockchain/chain_sync/src/sync.rs
+++ b/blockchain/chain_sync/src/sync.rs
@@ -1115,7 +1115,7 @@ mod tests {
             compute_msg_meta(&blockstore, &usm, &sm)
                 .unwrap()
                 .to_string(),
-            "bafy2bzacecgw6dqj4bctnbnyqfujltkwu7xc7ttaaato4i5miroxr4bayhfea"
+            "bafy2bzacecmda75ovposbdateg7eyhwij65zklgyijgcjwynlklmqazpwlhba"
         );
     }
 }
diff --git a/crypto/src/vrf.rs b/crypto/src/vrf.rs
index df86498f2b21..8939053711f6 100644
--- a/crypto/src/vrf.rs
+++ b/crypto/src/vrf.rs
@@ -37,6 +37,7 @@ impl VRFProof {
 pub mod json {
     use super::*;
     use serde::{de, Deserialize, Deserializer, Serialize, Serializer};
+    use std::borrow::Cow;
 
     pub fn serialize<S>(m: &VRFProof, serializer: S) -> Result<S::Ok, S::Error>
     where
@@ -49,7 +50,9 @@ pub mod json {
     where
         D: Deserializer<'de>,
     {
-        let s: String = Deserialize::deserialize(deserializer)?;
-        Ok(VRFProof::new(base64::decode(s).map_err(de::Error::custom)?))
+        let s: Cow<'de, str> = Deserialize::deserialize(deserializer)?;
+        Ok(VRFProof::new(
+            base64::decode(s.as_ref()).map_err(de::Error::custom)?,
+        ))
     }
 }
diff --git a/ipld/amt/src/bitmap.rs b/ipld/amt/src/bitmap.rs
index dd210b7db6ed..ab2e537e1f19 100644
--- a/ipld/amt/src/bitmap.rs
+++ b/ipld/amt/src/bitmap.rs
@@ -15,12 +15,7 @@ impl ser::Serialize for BitMap {
     where
         S: ser::Serializer,
     {
-        if self.b == 0 {
-            <[u8] as serde_bytes::Serialize>::serialize(&[], s)
-        } else {
-            let bitmap_bz = self.to_byte_array();
-            <[u8] as serde_bytes::Serialize>::serialize(&bitmap_bz, s)
-        }
+        <[u8] as serde_bytes::Serialize>::serialize(&[self.b], s)
     }
 }
 
@@ -29,17 +24,17 @@ impl<'de> de::Deserialize<'de> for BitMap {
     where
         D: de::Deserializer<'de>,
     {
-        let bz: Vec<u8> = serde_bytes::Deserialize::deserialize(deserializer)?;
+        let bz: &[u8] = serde_bytes::Deserialize::deserialize(deserializer)?;
 
-        if bz.is_empty() {
-            return Ok(BitMap::default());
+        if bz.len() != 1 {
+            return Err(de::Error::custom(&format!(
+                "Expected 1 bitmap byte, was {}",
+                bz.len()
+            )));
         }
 
         // Get bitmap byte from serialized bytes
-        let bmap: BitMap = bz
-            .get(0)
-            .map(|b| BitMap::new(*b))
-            .ok_or_else(|| de::Error::custom("Expected bitmap byte"))?;
+        let bmap = BitMap::new(bz[0]);
 
         Ok(bmap)
     }
diff --git a/ipld/tests/walk_tests.rs b/ipld/tests/walk_tests.rs
index 3d2447c4fa70..fed0eaf6cf7a 100644
--- a/ipld/tests/walk_tests.rs
+++ b/ipld/tests/walk_tests.rs
@@ -56,8 +56,8 @@ mod path_json {
     where
         D: Deserializer<'de>,
     {
-        let s: String = Deserialize::deserialize(deserializer)?;
-        Ok(Path::from(s.as_str()))
+        let s: std::borrow::Cow<'de, str> = Deserialize::deserialize(deserializer)?;
+        Ok(Path::from(s.as_ref()))
     }
 }
 
diff --git a/utils/bigint/src/bigint_ser.rs b/utils/bigint/src/bigint_ser.rs
index 324779736bd8..8e5f4dd0910e 100644
--- a/utils/bigint/src/bigint_ser.rs
+++ b/utils/bigint/src/bigint_ser.rs
@@ -37,11 +37,11 @@ pub fn deserialize<'de, D>(deserializer: D) -> Result<BigInt, D::Error>
 where
     D: serde::Deserializer<'de>,
 {
-    let mut bz: Vec<u8> = serde_bytes::Deserialize::deserialize(deserializer)?;
+    let bz: &[u8] = serde_bytes::Deserialize::deserialize(deserializer)?;
     if bz.is_empty() {
         return Ok(BigInt::default());
     }
-    let sign_byte = bz.remove(0);
+    let sign_byte = bz[0];
     let sign: Sign = match sign_byte {
         1 => Sign::Minus,
         0 => Sign::Plus,
@@ -51,5 +51,5 @@ where
             ));
         }
     };
-    Ok(BigInt::from_bytes_be(sign, &bz))
+    Ok(BigInt::from_bytes_be(sign, &bz[1..]))
 }
diff --git a/utils/bigint/src/biguint_ser.rs b/utils/bigint/src/biguint_ser.rs
index c617f3f652d7..c12c30ef37e6 100644
--- a/utils/bigint/src/biguint_ser.rs
+++ b/utils/bigint/src/biguint_ser.rs
@@ -35,16 +35,16 @@ pub fn deserialize<'de, D>(deserializer: D) -> Result<BigUint, D::Error>
 where
     D: serde::Deserializer<'de>,
 {
-    let mut bz: Vec<u8> = serde_bytes::Deserialize::deserialize(deserializer)?;
+    let bz: &[u8] = serde_bytes::Deserialize::deserialize(deserializer)?;
     if bz.is_empty() {
         return Ok(BigUint::default());
     }
 
-    if bz.remove(0) != 0 {
+    if bz.get(0) != Some(&0) {
         return Err(serde::de::Error::custom(
             "First byte must be 0 to decode as BigUint",
         ));
     }
 
-    Ok(BigUint::from_bytes_be(&bz))
+    Ok(BigUint::from_bytes_be(&bz[1..]))
 }
diff --git a/utils/bitfield/src/rleplus/mod.rs b/utils/bitfield/src/rleplus/mod.rs
index 95e0baa3e206..673dba665e76 100644
--- a/utils/bitfield/src/rleplus/mod.rs
+++ b/utils/bitfield/src/rleplus/mod.rs
@@ -85,7 +85,7 @@ impl<'de> Deserialize<'de> for BitField {
     where
         D: Deserializer<'de>,
     {
-        let bytes: Vec<u8> = serde_bytes::deserialize(deserializer)?;
+        let bytes: &[u8] = serde_bytes::deserialize(deserializer)?;
         Self::from_bytes(&bytes).map_err(serde::de::Error::custom)
     }
 }
diff --git a/vm/address/src/lib.rs b/vm/address/src/lib.rs
index b96006c3e0e7..51659eba5345 100644
--- a/vm/address/src/lib.rs
+++ b/vm/address/src/lib.rs
@@ -239,7 +239,7 @@ impl<'de> Deserialize<'de> for Address {
     where
         D: Deserializer<'de>,
     {
-        let bz: Vec<u8> = serde_bytes::Deserialize::deserialize(deserializer)?;
+        let bz: &[u8] = serde_bytes::Deserialize::deserialize(deserializer)?;
 
         // Create and return created address of unmarshalled bytes
         Address::from_bytes(&bz).map_err(de::Error::custom)