High-Performance Minecraft NBT Library for Morden C++

A blazing-fast C++ library for parsing, generating, and manipulating Minecraft Named Binary Tag (NBT) data with benchmarked speeds of 200 MB/s on modern CPUs.

Supported NBT format 📖

| NBT Format | Minecraft Edition | Support Status | | --------------------------------- | ---------------------- | ------------------ | | Little Endian Binary | Bedrock Edition | :white_check_mark: | | Little Endian Binary with Header | Bedrock Edition | :white_check_mark: | | Big Endian Binary | Java Edition | :white_check_mark: | | Big Endian Binary with Header | Java Edition | :white_check_mark: | | Bedrock Network (VarInt Encoding) | Bedrock Edition | :white_check_mark: | | Formatted String (SNBT) | Bedrock & Java Edition | :white_check_mark: |

Features ⚡

• Ultra-fast parsing - Achieves 200 MB/s processing speed on modern CPUs
• Complete NBT support - All NBT types (Java and Bedrock)
• Full SNBT support - Full SNBT support, include new SNBT format since Java Edition 1.21.5
• Zero-copy design - Minimal memory allocation during parsing
• Streaming interface - Process large NBT files with constant memory footprint
• Cross-platform - Windows, Linux, macOS support
• Endian-aware - Automatic little/big-endian conversion
• Zlib/Gzip support - Built-in compression handling
• Simple API - Intuitive interface inspired by standard libraries
• CFFI - Pure C API support.

Quick Start 🚀

using namespace nbt::literals::integral;

// Parsing NBT from file (Automatically detect NBT format and decompress)
auto nbt1 = nbt::io::parseFromFile("./level.dat");
// You can also specify the NBT format
// auto nbtRead = nbt::io::parseFromFile("./level.dat", NbtFileFormat::LittleEndian);

// Craate a CompoundTag in memory
nbt::CompoundTag nbt2 = {
    {"Byte",      64_b                                   },
    {"Short",     16384_s                                },
    {"Int",       12345678                               },
    {"Long",      5678900123456_l                        },
    {"Float",     3.14159f                               },
    {"Double",    1.23456789                             },
    {"String",    "homo string"                          },
    {"ByteArray", ByteArrayTag({2, 3, 4, 5, 6, 7, 8, 9}) },
    {"List",      ListTag()                              },
    {"Compound",  CompoundTag()                          },
    {"IntArray",  IntArrayTag({212345, 3765432, 4234567})},
    {"LongArray", LongArrayTag({45, 432, 244, 524})      },
};

nbt2.toBinaryNbt();   // to binary nbt format
nbt2.toNetworkNbt();  // to network nbt format

// Save NBT to file
nbt::io::saveToFile(nbt2, NbtFileFormat::LittleEndian);

Install and Using 🔧

Requirements

• C++23 compatible compiler (GCC 13+, Clang 17+, MSVC 2022+)
• Xmake 3.0.0+

Build Scripts

add_repositories("groupmountain-repo https://github.com/GroupMountain/xmake-repo.git")

add_requires("nbt")

Building from Source 🔧

• Build with Xmake

xmake --all

• If you want to use Cmake build system, you can generate CmakeLists.txt

xmake project -k cmake

Projects Using This Library 🏆

| Project | Link | | ---------------- | -------------------------------------------- | | ProtocolLib | https://github.com/GlacieTeam/ProtocolLib | | AntiXray | https://github.com/GlacieTeam/AntiXray | | RapidNBT | https://github.com/GlacieTeam/RapidNBT |

If you would like to add your project here, please create a pull request.

Contributing 🤝

Contributions are welcome! Please follow these steps:

1. Fork the repository and create your feature branch
2. Add tests for any new functionality
3. Submit a pull request with detailed description

License 📄

This project is licensed under the Mozilla Public License 2.0 (MPL-2.0).

Key Requirements:

• Modifications to this project's files must be released under MPL-2.0.
• Static/dynamic linking with closed-source projects is allowed (no requirement to disclose your own code).
• Patent protection is explicitly granted to all users.

For the full license text, see LICENSE file or visit MPL 2.0 Official Page.

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Copyright © 2025 GlacieTeam. All rights reserved.