diff --git a/contract_wasm_interface_parser/__init__.py b/contract_wasm_interface_parser/__init__.py
index c6cdcf7..4b14f91 100644
--- a/contract_wasm_interface_parser/__init__.py
+++ b/contract_wasm_interface_parser/__init__.py
@@ -10,11 +10,11 @@
 class ContractMetaData:
     """The contract metadata parsed from the Stellar Contract WASM."""
 
-    env_meta_base64: Optional[bytes] = None
+    env_meta_bytes: Optional[bytes] = None
     env_meta: List[SCEnvMetaEntry] = dataclasses.field(default_factory=list)
-    meta_base64: Optional[bytes] = None
+    meta_bytes: Optional[bytes] = None
     meta: List[SCMetaEntry] = dataclasses.field(default_factory=list)
-    spec_base64: Optional[bytes] = None
+    spec_bytes: Optional[bytes] = None
     spec: List[SCSpecEntry] = dataclasses.field(default_factory=list)
 
 
@@ -31,13 +31,13 @@ def parse_contract_metadata(wasm: Union[bytes, str]) -> ContractMetaData:
     metadata = ContractMetaData()
     for name, content in custom_sections:
         if name == "contractenvmetav0":
-            metadata.env_meta_base64 = content
+            metadata.env_meta_bytes = content
             metadata.env_meta = parse_entries(content, SCEnvMetaEntry)
         if name == "contractspecv0":
-            metadata.spec_base64 = content
+            metadata.spec_bytes = content
             metadata.spec = parse_entries(content, SCSpecEntry)
         if name == "contractmetav0":
-            metadata.meta_base64 = content
+            metadata.meta_bytes = content
             metadata.meta = parse_entries(content, SCMetaEntry)
     return metadata
 
diff --git a/pyproject.toml b/pyproject.toml
index 97cb7b5..6e21ff0 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "contract-wasm-interface-parser"
-version = "0.1.0"
+version = "0.2.0"
 description = "Contract interface metadata parser for binary Stellar WASM"
 authors = ["overcat <4catcode@gmail.com>"]
 license = "Apache License 2.0"
diff --git a/tests/__init__.py b/tests/__init__.py
index bf6edc4..8fdfc93 100644
--- a/tests/__init__.py
+++ b/tests/__init__.py
@@ -10,14 +10,14 @@ def test_parser(self):
         wasm = "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"
         metadata = parse_contract_metadata(wasm)
         expected = ContractMetaData(
-            env_meta_base64=b"\x00\x00\x00\x00\x00\x00\x00\x14\x00\x00\x00\x00",
+            env_meta_bytes=b"\x00\x00\x00\x00\x00\x00\x00\x14\x00\x00\x00\x00",
             env_meta=[
                 SCEnvMetaEntry(
                     kind=SCEnvMetaKind.SC_ENV_META_KIND_INTERFACE_VERSION,
                     interface_version=Uint64(uint64=85899345920),
                 )
             ],
-            meta_base64=b"\x00\x00\x00\x00\x00\x00\x00\x05rsver\x00\x00\x00\x00\x00\x00\x061.78.0\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08rssdkver\x00\x00\x00/20.3.1#ba045a57af971fc83e475746b59a503b7ef41649\x00",
+            meta_bytes=b"\x00\x00\x00\x00\x00\x00\x00\x05rsver\x00\x00\x00\x00\x00\x00\x061.78.0\x00\x00\x00\x00\x00\x00\x00\x00\x00\x08rssdkver\x00\x00\x00/20.3.1#ba045a57af971fc83e475746b59a503b7ef41649\x00",
             meta=[
                 SCMetaEntry(
                     kind=SCMetaKind.SC_META_V0, v0=SCMetaV0(key=b"rsver", val=b"1.78.0")
@@ -30,7 +30,7 @@ def test_parser(self):
                     ),
                 ),
             ],
-            spec_base64=b"\x00\x00\x00\x00\x00\x00\x00@Increment increments an internal counter, and returns the value.\x00\x00\x00\tincrement\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x04",
+            spec_bytes=b"\x00\x00\x00\x00\x00\x00\x00@Increment increments an internal counter, and returns the value.\x00\x00\x00\tincrement\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x04",
             spec=[
                 SCSpecEntry(
                     kind=SCSpecEntryKind.SC_SPEC_ENTRY_FUNCTION_V0,