diff --git a/src/server/blocks.rs b/src/server/blocks.rs
index 8c27d3b..78b274b 100644
--- a/src/server/blocks.rs
+++ b/src/server/blocks.rs
@@ -82,14 +82,19 @@ impl LastCommitInfo {
     }
 }
 
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
+#[repr(transparent)]
+pub struct HashID(
+    #[serde(serialize_with = "serialize_hex", deserialize_with = "from_hex")] pub Vec<u8>,
+);
+
 /// Relevant information regarding blocks
 #[derive(Debug, Serialize, Deserialize, PartialEq)]
 pub struct BlockInfo {
-    #[serde(serialize_with = "serialize_hex", deserialize_with = "from_hex")]
-    pub block_id: Vec<u8>,
+    pub block_id: HashID,
     pub header: Header,
     pub last_commit: Option<LastCommitInfo>,
-    pub tx_hashes: Vec<Vec<u8>>,
+    pub tx_hashes: Vec<HashID>,
 }
 
 impl From<BlockInfo> for Header {
@@ -236,7 +241,7 @@ impl TryFrom<&Row> for BlockInfo {
         };
 
         Ok(BlockInfo {
-            block_id,
+            block_id: HashID(block_id),
             header,
             last_commit,
             tx_hashes: vec![],
diff --git a/src/server/mod.rs b/src/server/mod.rs
index 7c13eb4..7701f59 100644
--- a/src/server/mod.rs
+++ b/src/server/mod.rs
@@ -43,9 +43,9 @@ async fn get_tx_hashes(
 ) -> Result<(), Error> {
     let rows = state.db.get_tx_hashes_block(hash).await?;
 
-    let mut tx_hashes: Vec<Vec<u8>> = vec![];
+    let mut tx_hashes: Vec<blocks::HashID> = vec![];
     for row in rows.iter() {
-        let hash: Vec<u8> = row.try_get("hash")?;
+        let hash = blocks::HashID(row.try_get("hash")?);
         tx_hashes.push(hash);
     }
 
diff --git a/tests/block_tests.rs b/tests/block_tests.rs
index 08092bd..de31012 100644
--- a/tests/block_tests.rs
+++ b/tests/block_tests.rs
@@ -33,7 +33,7 @@ mod block_tests {
 
         let header = response.json_body_as::<BlockInfo>().unwrap();
 
-        let hash_str = hex::encode(&header.block_id);
+        let hash_str = hex::encode(&header.block_id.0);
 
         // now retrieve same block but by hash:
         let new_header = hc