diff --git a/README.md b/README.md
index 12db110..2704f82 100644
--- a/README.md
+++ b/README.md
@@ -28,7 +28,7 @@ const NBT = require('mcnbt');
 There're several function for you to parse an NBT structure after you instantiating
 an object:
 
-+ `loadFromBuffer(buff, callback)`
++ `loadFromBuffer(buff, callback?)`: callback is optional
 + `loadFromZlibCompressedBuffer(buff, callback)`
 + `loadFromFile(filename, callback)`
 + `loadFromZlibCompressedFile(filename, callback)`
@@ -112,8 +112,7 @@ No extra method.
 
 ### TAGLong
 
-The value's type is long long ([bignum](https://github.com/justmoon/node-bignum)
-in js).
+The value's type is long (bigint in js).
 
 No extra method.
 
@@ -125,7 +124,7 @@ No extra method.
 
 ### TAGDouble
 
-The value's type is double (nbumer in js).
+The value's type is double (number in js).
 
 No extra method.
 
diff --git a/lib/base_tag.js b/lib/base_tag.js
index 33d85b7..5864903 100644
--- a/lib/base_tag.js
+++ b/lib/base_tag.js
@@ -1,7 +1,5 @@
 'use strict';
 
-const Long = require('long');
-
 const TAG_TYPE_OFFSET = 1;
 let _tagIds;
 
@@ -194,8 +192,8 @@ class BaseTag {
       return val;
     }
 
-    if (val instanceof Long) {
-      return val;
+    if (typeof val === 'bigint') {
+      return val.toString();
     }
 
     if (this.type === 'TAG_Int_Array' || this.type === 'TAG_Byte_Array') {
diff --git a/lib/bvffer.js b/lib/bvffer.js
deleted file mode 100644
index a89ee51..0000000
--- a/lib/bvffer.js
+++ /dev/null
@@ -1,104 +0,0 @@
-'use strict';
-
-const defaultPoolSize = 64 * 1024;
-if (Buffer.poolSize < defaultPoolSize) {
-  Buffer.poolSize = defaultPoolSize;
-}
-
-class Bvffer {
-  constructor(buffByteLength) {
-    /**
-     * Buffer store data
-     */
-    this.buffer = Buffer.allocUnsafe(buffByteLength);
-    /**
-     * data length in buffer
-     */
-    this.dataByteLength = 0;
-  }
-
-  get dataLength() {
-    return this.dataByteLength;
-  }
-
-  get buff() {
-    return this.buffer;
-  }
-
-  /**
-   * write buffer data to buffer
-   * @param {Buffer} value data to write
-   */
-  writeBuffer(value) {
-    this.writeUInt16BE(value.length);
-
-    value.copy(this.buffer, this.dataByteLength);
-    this.dataByteLength += value.length;
-  }
-
-  /**
-   * @param {number} value value
-   */
-  writeUInt8(value) {
-    this.buff[this.dataByteLength] = value;
-    this.dataByteLength += 1;
-  }
-
-  /**
-   * @param {number} value value
-   */
-  writeInt8(value) {
-    this.buff[this.dataByteLength] = value;
-    this.dataByteLength += 1;
-  }
-
-  /**
-   * @param {number} value value
-   */
-  writeUInt16BE(value) {
-    this.buffer.writeUInt16BE(value, this.dataByteLength);
-    this.dataByteLength += 2;
-  }
-
-  /**
-   * @param {number} value value
-   */
-  writeInt16BE(value) {
-    this.buffer.writeInt16BE(value, this.dataByteLength);
-    this.dataByteLength += 2;
-  }
-
-  /**
-   * @param {number} value value
-   */
-  writeUInt32BE(value) {
-    this.buffer.writeUInt32BE(value, this.dataByteLength);
-    this.dataByteLength += 4;
-  }
-
-  /**
-   * @param {number} value value
-   */
-  writeInt32BE(value) {
-    this.buffer.writeInt32BE(value, this.dataByteLength);
-    this.dataByteLength += 4;
-  }
-
-  /**
-   * @param {number} value value
-   */
-  writeDoubleBE(value) {
-    this.buffer.writeDoubleBE(value, this.dataByteLength);
-    this.dataByteLength += 8;
-  }
-
-  /**
-   * @param {number} value value
-   */
-  writeFloatBE(value) {
-    this.buffer.writeFloatBE(value, this.dataByteLength);
-    this.dataByteLength += 4;
-  }
-}
-
-exports.Bvffer = Bvffer;
diff --git a/lib/tags/byte_array.js b/lib/tags/byte_array.js
index 066d2dc..2115a36 100644
--- a/lib/tags/byte_array.js
+++ b/lib/tags/byte_array.js
@@ -44,7 +44,7 @@ class TAGByteArray extends BaseTag {
 
   /**
    * Write body to buffer
-   * @param {Bvffer} buff The buffer to write to
+   * @param {Buffer} buff The buffer to write to
    * @param {number} offset The offset to start writing from
    */
   writeBuffer(buff) {
diff --git a/lib/tags/compound.js b/lib/tags/compound.js
index b1b2d4b..26f2434 100644
--- a/lib/tags/compound.js
+++ b/lib/tags/compound.js
@@ -100,7 +100,7 @@ class TAGCompound extends BaseTag {
 
   /**
    * Write body to buffer
-   * @param {Bvffer} buff The buffer to write to
+   * @param {Buffer} buff The buffer to write to
    * @param {number} offset The offset to start writing to
    */
   writeBuffer(buff) {
diff --git a/lib/tags/int.js b/lib/tags/int.js
index 069122b..9c417d4 100644
--- a/lib/tags/int.js
+++ b/lib/tags/int.js
@@ -27,7 +27,7 @@ class TAGInt extends BaseTag {
 
   /**
    * Write body to buffer
-   * @param {Bvffer} buff The buffer to write to
+   * @param {Buffer} buff The buffer to write to
    */
   writeBuffer(buff) {
     buff.writeInt32BE(this.value);
diff --git a/lib/tags/long.js b/lib/tags/long.js
index f90f7eb..cafd70e 100644
--- a/lib/tags/long.js
+++ b/lib/tags/long.js
@@ -1,11 +1,10 @@
 'use strict';
 
 const BaseTag = require('../base_tag');
-const Long = require('long');
 
 const LONG_BOUND = {
-  MIN: Long.fromString('-9223372036854775808'),
-  MAX: Long.fromString('9223372036854775807'),
+  MIN: BigInt('-9223372036854775808'),
+  MAX: BigInt('9223372036854775807'),
 };
 
 class TAGLong extends BaseTag {
@@ -15,16 +14,12 @@ class TAGLong extends BaseTag {
   }
 
   _readBodyFromBuffer(buff, offset) {
-    const sliced = buff.slice(offset, offset + 8);
-    this.value = Long.fromBytesBE(sliced, true);
+    this.value = buff.readBigInt64BE(offset);
     return 8;
   }
 
   writeBuffer(buff) {
-    const bytes = this.value.toBytesBE();
-    for (let i = 0; i < 8; i++) {
-      buff.writeUInt8(bytes[i]);
-    }
+    buff.writeBigInt64BE(this.value);
   }
 
   toJSON() {
@@ -34,18 +29,18 @@ class TAGLong extends BaseTag {
   setValue(value) {
     let temp = -1;
     if (typeof value === 'string') {
-      temp = new Long(value);
-    } else if (value instanceof Long) {
-      temp = Long.fromString(value.toString());
+      temp = BigInt(value);
+    } else if (typeof value === 'bigint') {
+      temp = value;
     } else if (typeof value === 'number' && !isNaN(value)) {
-      temp = Long.fromNumber(value);
+      temp = BigInt(value);
     }
 
     if (temp === -1) {
       throw new Error('Wrong type to set TAG_Long\'s value.');
     }
 
-    if (temp.lessThan(LONG_BOUND.MIN) || temp.greaterThan(LONG_BOUND.MAX)) {
+    if (temp < LONG_BOUND.MIN || temp > LONG_BOUND.MAX) {
       throw new RangeError(
         'Value of TAG_Long should between -9223372036854775808 and ' +
         '9223372036854775807');
diff --git a/lib/tags/short.js b/lib/tags/short.js
index e6da2fe..40c037c 100644
--- a/lib/tags/short.js
+++ b/lib/tags/short.js
@@ -27,7 +27,7 @@ class TAGShort extends BaseTag {
 
   /**
    * Write body to buffer
-   * @param {Bvffer} buff The buffer to write to
+   * @param {Buffer} buff The buffer to write to
    */
   writeBuffer(buff) {
     buff.writeInt16BE(this.value);
diff --git a/nbt.js b/nbt.js
index 2c21c7c..fa219af 100644
--- a/nbt.js
+++ b/nbt.js
@@ -1,10 +1,11 @@
 'use strict';
 
-const fs = require('fs');
-const zlib = require('zlib');
+let fs;
+try { fs = require('fs'); } catch (e) { /* Not running on Node.js */ }
+let zlib;
+try { zlib = require('zlib'); } catch (e) { /* Not running on Node.js */ }
 
 const Tag = require('./lib/base_tag');
-const { Bvffer } = require('./lib/bvffer');
 
 /**
  * The NBT class
@@ -18,9 +19,10 @@ class NBT {
   /**
    * Load from buffer
    * @param {Buffer} buff The buffer to load from
-   * @param {(err?: Error) => void} callback The callback to call when done
+   * @param {(err?: Error) => void} [callback] The callback to call when done
    */
   loadFromBuffer(buff, callback) {
+    let err;
     try {
       this._buff = buff;
       let offset = 0;
@@ -33,10 +35,14 @@ class NBT {
         offset += len;
       }
     } catch (e) {
-      return callback(e);
+      err = e;
     }
 
-    callback();
+    if (callback) {
+      callback(err);
+    } else {
+      throw err;
+    }
   }
 
   /**
@@ -73,7 +79,7 @@ class NBT {
    * @return {Buffer} The buffer
    */
   writeToBuffer() {
-    const buff = new Bvffer(this.calcBufferLength());
+    const buff = new Buffer(this.calcBufferLength());
     for (const key in this.root) {
       if (!this.root.hasOwnProperty(key)) continue;
 
diff --git a/package.json b/package.json
index 29b0d59..148abdf 100644
--- a/package.json
+++ b/package.json
@@ -21,12 +21,8 @@
     "url": "https://github.com/XadillaX/mcnbt/issues"
   },
   "homepage": "https://github.com/XadillaX/mcnbt",
-  "dependencies": {
-    "long": "^4.0.0"
-  },
   "types": "types/nbt.d.ts",
   "devDependencies": {
-    "@types/long": "^4.0.1",
     "@types/node": "^17.0.18",
     "eslint": "^8.9.0",
     "eslint-config-egg": "^11.0.0",
diff --git a/test/archive.js b/test/archive.js
index 8b76224..f11ee26 100644
--- a/test/archive.js
+++ b/test/archive.js
@@ -3,11 +3,18 @@
 const fs = require('fs');
 const util = require('util');
 
-const Long = require('long');
 const should = require('should');
 
 const NBT = require('../nbt');
 
+function tryBigInt(value) {
+  try {
+    return BigInt(value);
+  } catch (e) {
+    return BigInt(0);
+  }
+}
+
 describe('Real archive test', function() {
   const archive = new NBT();
   let stdData = fs.readFileSync(__dirname + '/files/level.dat.json', {
@@ -58,7 +65,7 @@ describe('Real archive test', function() {
         } else if (typeof result === 'string') {
           if (result === '') {
             node.getType().should.match(/^TAG_String/);
-          } else if (Long.fromString(result).toString() === result) {
+          } else if (tryBigInt(result).toString() === result) {
             node.getType().should.match(/^TAG_(Long|String)$/);
           } else {
             node.getType().should.match(/^TAG_String$/);
diff --git a/test/bigtest_archive.js b/test/bigtest_archive.js
index c2c6ba6..3cd838f 100644
--- a/test/bigtest_archive.js
+++ b/test/bigtest_archive.js
@@ -3,11 +3,18 @@
 const fs = require('fs');
 const util = require('util');
 
-const Long = require('long');
 const should = require('should');
 
 const NBT = require('../nbt');
 
+function tryBigInt(value) {
+  try {
+    return BigInt(value);
+  } catch (e) {
+    return BigInt(0);
+  }
+}
+
 describe('Real bugtest archive test', function() {
   const archive = new NBT();
   const stdData = require('./files/bigtest.nbt.json');
@@ -57,7 +64,7 @@ describe('Real bugtest archive test', function() {
         } else if (typeof result === 'object' && !util.isArray(result)) {
           node.getType().should.be.eql('TAG_Compound');
         } else if (typeof result === 'string') {
-          if (Long.fromString(result).toString() === result) {
+          if (tryBigInt(result).toString() === result) {
             node.getType().should.match(/^TAG_(String|Long)$/);
           } else {
             node.getType().should.be.eql('TAG_String');
diff --git a/types/lib/bvffer.d.ts b/types/lib/bvffer.d.ts
deleted file mode 100644
index e9370bb..0000000
--- a/types/lib/bvffer.d.ts
+++ /dev/null
@@ -1,30 +0,0 @@
-/**
- * The Bvffer class
- */
-declare class Bvffer {
-  constructor(buffByteLength: number);
-
-  get dataLength(): number;
-
-  get buff(): Buffer;
-
-  writeBuffer(value): void;
-
-  writeUInt8(value): void;
-
-  writeInt8(value): void;
-
-  writeUInt16BE(value): void;
-
-  writeInt16BE(value): void;
-
-  writeUInt32BE(value): void;
-
-  writeInt32BE(value): void;
-
-  writeFloatBE(value): void;
-
-  writeDoubleBE(value): void;
-}
-
-export = Bvffer;
diff --git a/types/lib/tags/long.d.ts b/types/lib/tags/long.d.ts
index 09fdca6..bcfb8c4 100644
--- a/types/lib/tags/long.d.ts
+++ b/types/lib/tags/long.d.ts
@@ -1,9 +1,8 @@
 import BaseTag from '../base_tag.d';
-import Long from 'long';
 
 declare class TAGLong extends BaseTag {
-  getValue(): Long;
-  setValue(value: string | Long | number): void;
+  getValue(): bigint;
+  setValue(value: string | bigint | number): void;
 }
 
 export = TAGLong;
diff --git a/types/nbt.d.ts b/types/nbt.d.ts
index 8ee6cd1..4bd2da2 100644
--- a/types/nbt.d.ts
+++ b/types/nbt.d.ts
@@ -9,9 +9,9 @@ declare class NBT {
   /**
    * Load from buffer
    * @param {Buffer} buff The buffer to load from
-   * @param {(err?: Error) => void} callback The callback to call when done
+   * @param {(err?: Error) => void} [callback] The callback to call when done
    */
-  loadFromBuffer(buff: Buffer, callback: (err?: Error) => void): void;
+  loadFromBuffer(buff: Buffer, callback?: (err?: Error) => void): void;
   _buff: Buffer;
   /**
    * Load from compressed buffer