diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1284a19..edf550a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 ## 3.4.0
 
 - Stellar Address Support: Add support for stellar Contract address.
+- Fix incorrect CBOR encoding of large negative integers.
 
 ## 3.3.0
 
diff --git a/lib/cbor/cbor.dart b/lib/cbor/cbor.dart
index 6dee719..edfd53a 100644
--- a/lib/cbor/cbor.dart
+++ b/lib/cbor/cbor.dart
@@ -5,3 +5,5 @@ library cbor;
 export 'core/cbor.dart';
 
 export 'types/types.dart';
+
+export 'exception/exception.dart';
diff --git a/lib/cbor/core/cbor.dart b/lib/cbor/core/cbor.dart
index b38c8d9..4c9c91a 100644
--- a/lib/cbor/core/cbor.dart
+++ b/lib/cbor/core/cbor.dart
@@ -1,7 +1,7 @@
+import 'package:blockchain_utils/cbor/exception/exception.dart';
 import 'package:blockchain_utils/utils/utils.dart';
 import 'package:blockchain_utils/cbor/types/types.dart';
 import 'package:blockchain_utils/cbor/utils/cbor_utils.dart';
-import 'package:blockchain_utils/exception/exception.dart';
 
 /// An abstract class representing a CBOR (Concise Binary Object Representation) object.
 /// CBOR objects can hold various data types and optional tags, providing a flexible way
@@ -49,12 +49,15 @@ abstract class CborObject {
     } else if (value is List<List<int>>) {
       return CborDynamicBytesValue(value);
     } else if (value is Map) {
-      return CborMapValue.fixedLength(value);
+      return CborMapValue.fixedLength({
+        for (final i in value.entries)
+          CborObject.fromDynamic(i.key): CborObject.fromDynamic(i.value)
+      });
     } else if (value is List<dynamic>) {
       return CborListValue.fixedLength(
           value.map((e) => CborObject.fromDynamic(e)).toList());
     }
-    throw UnimplementedError("does not supported");
+    throw const CborException("does not supported");
   }
 }
 
@@ -73,7 +76,7 @@ abstract class CborNumeric implements CborObject {
     } else if (val is CborSafeIntValue) {
       return val.value;
     }
-    throw const ArgumentException("invalid cbornumeric");
+    throw const CborException("invalid cbornumeric");
   }
 
   /// Convert the CborNumeric object to an integer.
diff --git a/lib/cbor/exception/exception.dart b/lib/cbor/exception/exception.dart
new file mode 100644
index 0000000..c6f804c
--- /dev/null
+++ b/lib/cbor/exception/exception.dart
@@ -0,0 +1,6 @@
+import 'package:blockchain_utils/exception/exceptions.dart';
+
+class CborException extends BlockchainUtilsException {
+  const CborException(String message, {Map<String, dynamic>? details})
+      : super(message, details: details);
+}
diff --git a/lib/cbor/types/bytes.dart b/lib/cbor/types/bytes.dart
index 72b9e76..2e8a0d1 100644
--- a/lib/cbor/types/bytes.dart
+++ b/lib/cbor/types/bytes.dart
@@ -10,8 +10,6 @@ class CborBytesValue implements CborObject {
   /// It accepts the bytes value.
   CborBytesValue(List<int> value) : value = value.asImmutableBytes;
 
-  /// The value as a List<int>.
-  @override
   final List<int> value;
 
   /// Encode the value into CBOR bytes
@@ -51,6 +49,8 @@ class CborDynamicBytesValue implements CborObject {
 
   @override
   final List<List<int>> value;
+  // @override
+  // List<List<int>> get value => _value;
 
   /// Encode the value into CBOR bytes
   @override
@@ -82,7 +82,7 @@ class CborDynamicBytesValue implements CborObject {
   operator ==(other) {
     if (other is! CborDynamicBytesValue) return false;
 
-    return value == other.value;
+    return CompareUtils.iterableIsEqual(value, other.value);
   }
 
   /// ovveride hash code
diff --git a/lib/cbor/types/cbor_tag.dart b/lib/cbor/types/cbor_tag.dart
index 3789e5a..1eb3e6c 100644
--- a/lib/cbor/types/cbor_tag.dart
+++ b/lib/cbor/types/cbor_tag.dart
@@ -22,7 +22,7 @@ class CborTagValue<T> implements CborObject {
   List<int> encode() {
     final bytes = CborBytesTracker();
     bytes.pushTags(tags);
-    final obj = CborObject.fromDynamic(value).encode();
+    final obj = CborObject.fromDynamic(_value).encode();
     bytes.pushBytes(obj);
     return bytes.toBytes();
   }
diff --git a/lib/cbor/types/decimal.dart b/lib/cbor/types/decimal.dart
index 0d3eef4..70ff400 100644
--- a/lib/cbor/types/decimal.dart
+++ b/lib/cbor/types/decimal.dart
@@ -13,9 +13,7 @@ class CborDecimalFracValue implements CborObject {
 
   /// Create a CborBigFloatValue from two CborNumeric values representing the exponent and mantissa.
   factory CborDecimalFracValue.fromCborNumeric(
-    CborNumeric exponent,
-    CborNumeric mantissa,
-  ) {
+      CborNumeric exponent, CborNumeric mantissa) {
     return CborDecimalFracValue(CborNumeric.getCborNumericValue(exponent),
         CborNumeric.getCborNumericValue(mantissa));
   }
diff --git a/lib/cbor/types/int.dart b/lib/cbor/types/int.dart
index 8f2d26d..ff6ae98 100644
--- a/lib/cbor/types/int.dart
+++ b/lib/cbor/types/int.dart
@@ -1,4 +1,5 @@
 import 'package:blockchain_utils/cbor/core/cbor.dart';
+import 'package:blockchain_utils/cbor/exception/exception.dart';
 import 'package:blockchain_utils/cbor/utils/dynamic_bytes.dart';
 import 'package:blockchain_utils/cbor/core/tags.dart';
 import 'package:blockchain_utils/utils/utils.dart';
@@ -20,10 +21,13 @@ class CborIntValue implements CborNumeric {
   List<int> encode() {
     final bytes = CborBytesTracker();
     if (value.bitLength > 31 && value.isNegative) {
-      final value = (~BigInt.parse(this.value.toString())).toInt();
-      bytes.pushInt(MajorTags.negInt, value);
+      final value = (~BigInt.parse(this.value.toString()));
+      if (!value.isValidInt) {
+        throw CborException("Value is to large for encoding as CborInteger",
+            details: {"value": this.value.toString()});
+      }
+      bytes.pushInt(MajorTags.negInt, value.toInt());
     } else {
-      // print("is here lower!");
       bytes.pushInt(value.isNegative ? MajorTags.negInt : MajorTags.posInt,
           value.isNegative ? ~value : value);
     }
diff --git a/lib/cbor/types/list.dart b/lib/cbor/types/list.dart
index f43157e..9f8ab92 100644
--- a/lib/cbor/types/list.dart
+++ b/lib/cbor/types/list.dart
@@ -1,4 +1,3 @@
-import 'package:blockchain_utils/helper/helper.dart';
 import 'package:blockchain_utils/utils/utils.dart';
 import 'package:blockchain_utils/cbor/utils/dynamic_bytes.dart';
 import 'package:blockchain_utils/cbor/core/tags.dart';
@@ -9,18 +8,13 @@ class CborListValue<T> implements CborObject {
   /// Constructor for creating a CborListValue instance with the provided parameters.
   /// It accepts the List of all cbor encodable value.
   ///
-  CborListValue.fixedLength(List<T> value)
-      : value = value.immutable,
-        _isFixedLength = true;
+  CborListValue.fixedLength(this.value) : _isFixedLength = true;
 
   /// Constructor for creating a CborListValue instance with the provided parameters.
   /// It accepts the List of all cbor encodable value.
   /// this method encode values with indefinite tag.
-  CborListValue.dynamicLength(List<T> value)
-      : value = value.immutable,
-        _isFixedLength = false;
+  CborListValue.dynamicLength(this.value) : _isFixedLength = false;
 
-  /// value as List
   @override
   final List<T> value;
 
diff --git a/lib/cbor/types/map.dart b/lib/cbor/types/map.dart
index 19aa0db..2a60389 100644
--- a/lib/cbor/types/map.dart
+++ b/lib/cbor/types/map.dart
@@ -1,4 +1,3 @@
-import 'package:blockchain_utils/helper/helper.dart';
 import 'package:blockchain_utils/utils/utils.dart';
 import 'package:blockchain_utils/cbor/utils/dynamic_bytes.dart';
 import 'package:blockchain_utils/cbor/core/tags.dart';
@@ -8,16 +7,12 @@ import 'package:blockchain_utils/cbor/core/cbor.dart';
 class CborMapValue<K, V> implements CborObject {
   /// Constructor for creating a CborMapValue instance with the provided parameters.
   /// It accepts the Map with all cbor encodable key and value.
-  CborMapValue.fixedLength(Map<K, V> value)
-      : value = value.immutable,
-        _isFixedLength = true;
+  CborMapValue.fixedLength(this.value) : _isFixedLength = true;
 
   /// Constructor for creating a CborMapValue instance with the provided parameters.
   /// It accepts the Map with all cbor encodable key and value.
   /// this method encode values with indefinite tag.
-  CborMapValue.dynamicLength(Map<K, V> value)
-      : value = value.immutable,
-        _isFixedLength = false;
+  CborMapValue.dynamicLength(this.value) : _isFixedLength = false;
 
   /// value as Map
   @override
diff --git a/lib/cbor/types/set.dart b/lib/cbor/types/set.dart
index f11655b..18fbf5b 100644
--- a/lib/cbor/types/set.dart
+++ b/lib/cbor/types/set.dart
@@ -7,7 +7,7 @@ import 'package:blockchain_utils/cbor/core/cbor.dart';
 class CborSetValue<T> implements CborObject {
   /// Constructor for creating a CborSetValue instance with the provided parameters.
   /// It accepts a set of all encodable cbor object.
-  CborSetValue(Set<T> value) : value = Set.unmodifiable(value);
+  CborSetValue(this.value);
 
   /// value as set
   @override
diff --git a/lib/cbor/types/string.dart b/lib/cbor/types/string.dart
index b022d96..d94f4d8 100644
--- a/lib/cbor/types/string.dart
+++ b/lib/cbor/types/string.dart
@@ -61,7 +61,6 @@ class CborIndefiniteStringValue extends CborString {
   /// It accepts a List<String> value.
   CborIndefiniteStringValue(List<String> value) : value = value.immutable;
 
-  /// value as List<String>
   @override
   final List<String> value;
 
diff --git a/lib/cbor/utils/cbor_utils.dart b/lib/cbor/utils/cbor_utils.dart
index 2afaa1d..97acb7f 100644
--- a/lib/cbor/utils/cbor_utils.dart
+++ b/lib/cbor/utils/cbor_utils.dart
@@ -1,9 +1,9 @@
 import 'dart:typed_data';
 import 'package:blockchain_utils/cbor/core/cbor.dart';
+import 'package:blockchain_utils/cbor/exception/exception.dart';
 import 'package:blockchain_utils/cbor/types/types.dart';
 import 'package:blockchain_utils/cbor/utils/float_utils.dart';
 import 'package:blockchain_utils/cbor/core/tags.dart';
-import 'package:blockchain_utils/exception/exception.dart';
 import 'package:blockchain_utils/utils/utils.dart';
 
 class CborUtils {
@@ -23,7 +23,7 @@ class CborUtils {
       // Split the string into the date and offset parts
       final parts = dateTimeString.split('+');
       if (parts.length != 2) {
-        throw MessageException("Invalid format: $dateTimeString");
+        throw CborException("Invalid RFC3339 format: $dateTimeString");
       }
       final datePart = DateTime.parse(parts[0]);
       return datePart;
@@ -66,11 +66,11 @@ class CborUtils {
           }
           return _decodeArray(cborBytes, i, info, tags);
         default:
-          throw ArgumentException(
+          throw CborException(
               "invalid or unsuported cbor tag major: $majorTag ");
       }
     }
-    throw const ArgumentException("invalid or unsuported cbor tag");
+    throw const CborException("invalid or unsuported cbor tag");
   }
 
   static Tuple<List<int>, int> _parsBytes(int info, List<int> cborBytes) {
@@ -96,7 +96,7 @@ class CborUtils {
       }
       return Tuple(decode, len + 1);
     } else {
-      throw ArgumentException('Invalid additional info for int: $info');
+      throw CborException('Invalid additional info for int: $info');
     }
   }
 
@@ -254,7 +254,7 @@ class CborUtils {
       List<CborObject> objects, List<int> tags) {
     objects = objects.whereType<CborNumeric>().toList();
     if (objects.length != 2) {
-      throw const MessageException("invalid bigFloat array length");
+      throw const CborException("invalid bigFloat array length");
     }
     if (BytesUtils.bytesEqual(tags, CborTags.decimalFrac)) {
       tags.clear();
@@ -313,7 +313,7 @@ class CborUtils {
         offset = offset + 8;
         break;
       default:
-        throw const MessageException("Invalid simpleOrFloatTags");
+        throw const CborException("Invalid simpleOrFloatTags");
     }
     if (BytesUtils.bytesEqual(tags, CborTags.dateEpoch)) {
       final dt = DateTime.fromMillisecondsSinceEpoch((val * 1000).round());
diff --git a/lib/cbor/utils/float_utils.dart b/lib/cbor/utils/float_utils.dart
index d9d496e..79756e3 100644
--- a/lib/cbor/utils/float_utils.dart
+++ b/lib/cbor/utils/float_utils.dart
@@ -17,7 +17,7 @@ import 'dart:math' as math;
 import 'dart:typed_data';
 
 import 'package:blockchain_utils/cbor/core/tags.dart';
-import 'package:blockchain_utils/exception/exception.dart';
+import 'package:blockchain_utils/cbor/exception/exception.dart';
 import 'package:blockchain_utils/utils/utils.dart';
 
 // Enum representing different floating-point formats and their characteristics.
@@ -60,7 +60,7 @@ class FloatLength {
     if (index >= 0 && index < values.length) {
       return values[index];
     }
-    throw MessageException('Index out of bounds', details: {"input": index});
+    throw CborException('Index out of bounds', details: {"input": index});
   }
 }
 
@@ -242,13 +242,13 @@ class FloatUtils {
     switch (decodFloatType) {
       case FloatLength.bytes16:
         if (!isLessThan16) {
-          throw const ArgumentException("overflow bytes");
+          throw const CborException("overflow bytes");
         }
         bytes = _encodeFloat16(endianness);
         break;
       case FloatLength.bytes32:
         if (!isLessThan32) {
-          throw const ArgumentException("overflow bytes");
+          throw const CborException("overflow bytes");
         }
         bytes = _encodeFloat32(endianness);
         break;
@@ -262,7 +262,7 @@ class FloatUtils {
   /// Decode a 16-bit floating-point value from a byte array and return it as a double.
   static double floatFromBytes16(List<int> bytes) {
     if (bytes.length != 2) {
-      throw const ArgumentException(
+      throw const CborException(
           'Input byte array must be exactly 2 bytes long for Float16');
     }
 
diff --git a/lib/utils/compare/compare.dart b/lib/utils/compare/compare.dart
index 67d1a3d..59a02f8 100644
--- a/lib/utils/compare/compare.dart
+++ b/lib/utils/compare/compare.dart
@@ -21,7 +21,15 @@ class CompareUtils {
 
     /// Compare the individual byte values in 'a' and 'b'.
     for (int index = 0; index < a.length; index += 1) {
-      if (a.elementAt(index) != b.elementAt(index)) {
+      final valueA = a.elementAt(index);
+      final valueB = b.elementAt(index);
+      if (valueA is Map && valueB is Map) {
+        // Recursively compare maps
+        if (!mapIsEqual(valueA, valueB)) return false;
+      } else if (valueA is Iterable && valueB is Iterable) {
+        // Recursively compare iterables
+        if (!iterableIsEqual(valueA, valueB)) return false;
+      } else if (valueA != valueB) {
         return false;
       }
     }
@@ -29,4 +37,33 @@ class CompareUtils {
     /// If no differences were found, the lists are equal.
     return true;
   }
+
+  static bool mapIsEqual<K, V>(Map<K, V>? a, Map<K, V>? b) {
+    // Handle null comparison
+    if (a == null) return b == null;
+    if (b == null || a.length != b.length) return false;
+
+    // Check if 'a' and 'b' are identical objects
+    if (identical(a, b)) return true;
+
+    // Compare the entries in 'a' and 'b'
+    for (final key in a.keys) {
+      if (!b.containsKey(key)) return false;
+
+      final valueA = a[key];
+      final valueB = b[key];
+
+      if (valueA is Map && valueB is Map) {
+        // Recursively compare maps
+        if (!mapIsEqual(valueA, valueB)) return false;
+      } else if (valueA is Iterable && valueB is Iterable) {
+        // Recursively compare iterables
+        if (!iterableIsEqual(valueA, valueB)) return false;
+      } else if (valueA != valueB) {
+        return false;
+      }
+    }
+
+    return true;
+  }
 }