diff --git a/starknet-core/src/types/contract/mod.rs b/starknet-core/src/types/contract/mod.rs
index 1d626b42..d7ee6d62 100644
--- a/starknet-core/src/types/contract/mod.rs
+++ b/starknet-core/src/types/contract/mod.rs
@@ -83,8 +83,8 @@ pub struct CompiledClass {
     /// Represents the structure of the bytecode segments, using a nested list of segment lengths.
     /// For example, [2, [3, 4]] represents a bytecode with 2 segments, the first is a leaf of
     /// length 2 and the second is a node with 2 children of lengths 3 and 4.
-    #[serde(default, skip_serializing_if = "Vec::is_empty")]
-    pub bytecode_segment_lengths: Vec<IntOrList>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub bytecode_segment_lengths: Option<IntOrList>,
     /// Hints for non-determinism.
     pub hints: Vec<Hint>,
     /// Same as `hints` but represented in Python code, which can be generated by the compiler but
@@ -658,42 +658,45 @@ impl CompiledClass {
         );
 
         // Hashes bytecode
-        hasher.update(if self.bytecode_segment_lengths.is_empty() {
-            // Pre-Sierra-1.5.0 compiled classes
-            poseidon_hash_many(&self.bytecode)
-        } else {
-            // `bytecode_segment_lengths` was added since Sierra 1.5.0 and changed hash calculation.
-            // This implementation here is basically a direct translation of the Python code from
-            // `cairo-lang` v0.13.1. The goal was simply to have a working implementation as quickly
-            // as possible. There should be some optimizations to be made here.
-            // TODO: review how this can be optimized
-
-            // NOTE: this looks extremely inefficient. Maybe just use a number for tracking instead?
-            let mut rev_visited_pcs: Vec<u64> = (0..(self.bytecode.len() as u64)).rev().collect();
-
-            let (res, total_len) = Self::create_bytecode_segment_structure_inner(
-                &self.bytecode,
-                &IntOrList::List(self.bytecode_segment_lengths.clone()),
-                &mut rev_visited_pcs,
-                &mut 0,
-            )?;
-
-            if total_len != self.bytecode.len() as u64 {
-                return Err(ComputeClassHashError::BytecodeSegmentLengthMismatch(
-                    BytecodeSegmentLengthMismatchError {
-                        segment_length: total_len as usize,
-                        bytecode_length: self.bytecode.len(),
-                    },
-                ));
-            }
-            if !rev_visited_pcs.is_empty() {
-                return Err(ComputeClassHashError::PcOutOfRange(PcOutOfRangeError {
-                    pc: rev_visited_pcs[rev_visited_pcs.len() - 1],
-                }));
-            }
+        hasher.update(
+            if let Some(bytecode_segment_lengths) = self.bytecode_segment_lengths.clone() {
+                // `bytecode_segment_lengths` was added since Sierra 1.5.0 and changed hash calculation.
+                // This implementation here is basically a direct translation of the Python code from
+                // `cairo-lang` v0.13.1. The goal was simply to have a working implementation as quickly
+                // as possible. There should be some optimizations to be made here.
+                // TODO: review how this can be optimized
+
+                // NOTE: this looks extremely inefficient. Maybe just use a number for tracking instead?
+                let mut rev_visited_pcs: Vec<u64> =
+                    (0..(self.bytecode.len() as u64)).rev().collect();
+
+                let (res, total_len) = Self::create_bytecode_segment_structure_inner(
+                    &self.bytecode,
+                    &bytecode_segment_lengths,
+                    &mut rev_visited_pcs,
+                    &mut 0,
+                )?;
+
+                if total_len != self.bytecode.len() as u64 {
+                    return Err(ComputeClassHashError::BytecodeSegmentLengthMismatch(
+                        BytecodeSegmentLengthMismatchError {
+                            segment_length: total_len as usize,
+                            bytecode_length: self.bytecode.len(),
+                        },
+                    ));
+                }
+                if !rev_visited_pcs.is_empty() {
+                    return Err(ComputeClassHashError::PcOutOfRange(PcOutOfRangeError {
+                        pc: rev_visited_pcs[rev_visited_pcs.len() - 1],
+                    }));
+                }
 
-            res.hash()
-        });
+                res.hash()
+            } else {
+                // Pre-Sierra-1.5.0 compiled classes
+                poseidon_hash_many(&self.bytecode)
+            },
+        );
 
         Ok(hasher.finalize())
     }
@@ -1022,6 +1025,7 @@ mod tests {
             include_str!("../../../test-data/contracts/cairo2/artifacts/abi_types_sierra.txt"),
             include_str!("../../../test-data/contracts/cairo2/artifacts/erc20_sierra.txt"),
             include_str!("../../../test-data/contracts/cairo2.6/artifacts/erc20_sierra.txt"),
+            include_str!("../../../test-data/contracts/cairo2.6/artifacts/trivial_sierra.txt"),
         ] {
             let direct_deser = serde_json::from_str::<SierraClass>(raw_artifact).unwrap();
             let via_contract_artifact = match serde_json::from_str::<ContractArtifact>(raw_artifact)
@@ -1047,6 +1051,7 @@ mod tests {
             include_str!("../../../test-data/contracts/cairo2/artifacts/abi_types_compiled.txt"),
             include_str!("../../../test-data/contracts/cairo2/artifacts/erc20_compiled.txt"),
             include_str!("../../../test-data/contracts/cairo2.6/artifacts/erc20_compiled.txt"),
+            include_str!("../../../test-data/contracts/cairo2.6/artifacts/trivial_compiled.txt"),
         ] {
             let direct_deser = serde_json::from_str::<CompiledClass>(raw_artifact).unwrap();
             let via_contract_artifact = match serde_json::from_str::<ContractArtifact>(raw_artifact)
@@ -1133,6 +1138,12 @@ mod tests {
                 include_str!("../../../test-data/contracts/cairo2.6/artifacts/erc20_compiled.txt"),
                 include_str!("../../../test-data/contracts/cairo2.6/artifacts/erc20.hashes.json"),
             ),
+            (
+                include_str!(
+                    "../../../test-data/contracts/cairo2.6/artifacts/trivial_compiled.txt"
+                ),
+                include_str!("../../../test-data/contracts/cairo2.6/artifacts/trivial.hashes.json"),
+            ),
         ] {
             let compiled_class = serde_json::from_str::<CompiledClass>(raw_artifact).unwrap();
             let computed_hash = compiled_class.class_hash().unwrap();
diff --git a/starknet-core/test-data/contracts/cairo2.6/artifacts/trivial.hashes.json b/starknet-core/test-data/contracts/cairo2.6/artifacts/trivial.hashes.json
new file mode 100644
index 00000000..8fe9ca8c
--- /dev/null
+++ b/starknet-core/test-data/contracts/cairo2.6/artifacts/trivial.hashes.json
@@ -0,0 +1,4 @@
+{
+  "sierra_class_hash": "0x7585639b4e793743860f2761d81e070157ae8d0fc8e518a8cd9069eb2a40010",
+  "compiled_class_hash": "0x317d3ac2cf840e487b6d0014a75f0cf507dff0bc143c710388e323487089bfa"
+}
diff --git a/starknet-core/test-data/contracts/cairo2.6/artifacts/trivial_compiled.txt b/starknet-core/test-data/contracts/cairo2.6/artifacts/trivial_compiled.txt
new file mode 100644
index 00000000..09fb9b21
--- /dev/null
+++ b/starknet-core/test-data/contracts/cairo2.6/artifacts/trivial_compiled.txt
@@ -0,0 +1,12 @@
+{
+  "prime": "0x800000000000011000000000000000000000000000000000000000000000001",
+  "compiler_version": "2.6.2",
+  "bytecode": [],
+  "bytecode_segment_lengths": 0,
+  "hints": [],
+  "entry_points_by_type": {
+    "EXTERNAL": [],
+    "L1_HANDLER": [],
+    "CONSTRUCTOR": []
+  }
+}
\ No newline at end of file
diff --git a/starknet-core/test-data/contracts/cairo2.6/artifacts/trivial_sierra.txt b/starknet-core/test-data/contracts/cairo2.6/artifacts/trivial_sierra.txt
new file mode 100644
index 00000000..068b9022
--- /dev/null
+++ b/starknet-core/test-data/contracts/cairo2.6/artifacts/trivial_sierra.txt
@@ -0,0 +1,34 @@
+{
+  "sierra_program": [
+    "0x1",
+    "0x5",
+    "0x0",
+    "0x2",
+    "0x6",
+    "0x2",
+    "0x1",
+    "0xff",
+    "0x0",
+    "0x4",
+    "0x0"
+  ],
+  "sierra_program_debug_info": {
+    "type_names": [],
+    "libfunc_names": [],
+    "user_func_names": []
+  },
+  "contract_class_version": "0.1.0",
+  "entry_points_by_type": {
+    "EXTERNAL": [],
+    "L1_HANDLER": [],
+    "CONSTRUCTOR": []
+  },
+  "abi": [
+    {
+      "type": "event",
+      "name": "trivial::trivial::Trivial::Event",
+      "kind": "enum",
+      "variants": []
+    }
+  ]
+}
\ No newline at end of file
diff --git a/starknet-core/test-data/contracts/cairo2.6/contracts/trivial.cairo b/starknet-core/test-data/contracts/cairo2.6/contracts/trivial.cairo
new file mode 100644
index 00000000..1e978c3d
--- /dev/null
+++ b/starknet-core/test-data/contracts/cairo2.6/contracts/trivial.cairo
@@ -0,0 +1,10 @@
+#[starknet::contract]
+mod Trivial {
+    #[storage]
+    struct Storage {}
+
+    #[abi(embed_v0)]
+    fn something(ref self: ContractState) -> felt252 {
+        1
+    }
+}
diff --git a/starknet-core/test-data/contracts/cairo2.6/docker_entry_compile.sh b/starknet-core/test-data/contracts/cairo2.6/docker_entry_compile.sh
index da07484a..51ba4d14 100755
--- a/starknet-core/test-data/contracts/cairo2.6/docker_entry_compile.sh
+++ b/starknet-core/test-data/contracts/cairo2.6/docker_entry_compile.sh
@@ -11,3 +11,4 @@ compile () {
 }
 
 compile "/contracts/erc20.cairo" "/artifacts/erc20"
+compile "/contracts/trivial.cairo" "/artifacts/trivial"
diff --git a/starknet-core/test-data/contracts/cairo2.6/docker_entry_hashes.sh b/starknet-core/test-data/contracts/cairo2.6/docker_entry_hashes.sh
index c42c4cb5..ba0c8d2c 100755
--- a/starknet-core/test-data/contracts/cairo2.6/docker_entry_hashes.sh
+++ b/starknet-core/test-data/contracts/cairo2.6/docker_entry_hashes.sh
@@ -9,3 +9,4 @@ hash () {
 }
 
 hash "/artifacts/erc20"
+hash "/artifacts/trivial"