TDLib (Telegram Database library) is a cross-platform library for building Telegram clients. It can be easily used from almost any programming language.

• Features
• Examples and documentation
• Dependencies
• Building
• Using in CMake C++ projects
• Using in Java projects
• Using in .NET projects
• Using with other programming languages
• License

TDLib has many advantages. Notably TDLib is:

• Cross-platform: TDLib can be used on Android, iOS, Windows, macOS, Linux, FreeBSD, OpenBSD, NetBSD, illumos, Windows Phone, WebAssembly, watchOS, tvOS, visionOS, Tizen, Cygwin. It should also work on other *nix systems with or without minimal effort.
• Multilanguage: TDLib can be easily used with any programming language that is able to execute C functions. Additionally, it already has native Java (using JNI) bindings and .NET (using C++/CLI and C++/CX) bindings.
• Easy to use: TDLib takes care of all network implementation details, encryption and local data storage.
• High-performance: in the Telegram Bot API, each TDLib instance handles more than 25000 active bots simultaneously.
• Well-documented: all TDLib API methods and public interfaces are fully documented.
• Consistent: TDLib guarantees that all updates are delivered in the right order.
• Reliable: TDLib remains stable on slow and unreliable Internet connections.
• Secure: all local data is encrypted using a user-provided encryption key.
• Fully-asynchronous: requests to TDLib don't block each other or anything else, responses are sent when they are available.

See our Getting Started tutorial for a description of basic TDLib concepts.

Take a look at our examples.

See a TDLib build instructions generator for detailed instructions on how to build TDLib.

See description of our JSON, C++, Java and .NET interfaces.

See the td_api.tl scheme or the automatically generated HTML documentation for a list of all available TDLib methods and classes.

TDLib depends on:

• C++14 compatible compiler (Clang 3.4+, GCC 4.9+, MSVC 19.0+ (Visual Studio 2015+), Intel C++ Compiler 17+)
• OpenSSL
• zlib
• gperf (build only)
• CMake (3.0.2+, build only)
• PHP (optional, for documentation generation)

The simplest way to build TDLib is to use our TDLib build instructions generator. You need only to choose your programming language and target operating system to receive complete build instructions.

In general, you need to install all TDLib dependencies, enter directory containing TDLib sources and compile them using CMake:

mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
cmake --build .

To build TDLib on low memory devices you can run SplitSource.php script before compiling main TDLib source code and compile only needed targets:

mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
cmake --build . --target prepare_cross_compiling
cd ..
php SplitSource.php
cd build
cmake --build . --target tdjson
cmake --build . --target tdjson_static
cd ..
php SplitSource.php --undo

In our tests clang 6.0 with libc++ required less than 500 MB of RAM per file and GCC 4.9/6.3 used less than 1 GB of RAM per file.

For C++ projects that use CMake, the best approach is to build TDLib as part of your project or to install it system-wide.

There are several libraries that you could use in your CMake project:

• Td::TdJson, Td::TdJsonStatic — dynamic and static version of a JSON interface. This has a simple C interface, so it can be easily used with any programming language that is able to execute C functions. See td_json_client documentation for more information.
• Td::TdStatic — static library with C++ interface for general usage. See ClientManager and Client documentation for more information.

For example, part of your CMakeLists.txt may look like this:

add_subdirectory(td)
target_link_libraries(YourTarget PRIVATE Td::TdStatic)

Or you could install TDLib and then reference it in your CMakeLists.txt like this:

find_package(Td 1.8.40 REQUIRED)
target_link_libraries(YourTarget PRIVATE Td::TdStatic)

See example/cpp/CMakeLists.txt.

TDLib provides native Java interface through JNI. To enable it, specify option -DTD_ENABLE_JNI=ON to CMake.

See example/java for example of using TDLib from Java and detailed build and usage instructions.

TDLib provides native .NET interface through C++/CLI and C++/CX. To enable it, specify option -DTD_ENABLE_DOTNET=ON to CMake. .NET Core supports C++/CLI only since version 3.1 and only on Windows, so if older .NET Core is used or portability is needed, then TDLib JSON interface should be used through P/Invoke instead.

See example/csharp for example of using TDLib from C# and detailed build and usage instructions. See example/uwp for example of using TDLib from C# UWP application and detailed build and usage instructions for Visual Studio Extension "TDLib for Universal Windows Platform".

When TDLib is built with TD_ENABLE_DOTNET option enabled, C++ documentation is removed from some files. You need to checkout these files to return C++ documentation back:

git checkout td/telegram/Client.h td/telegram/Log.h td/tl/TlObject.h

TDLib provides efficient native C++, Java, and .NET interfaces. But for most use cases we suggest to use the JSON interface, which can be easily used with any programming language that is able to execute C functions. See td_json_client documentation for detailed JSON interface description, the td_api.tl scheme or the automatically generated HTML documentation for a list of all available TDLib methods and classes.

TDLib JSON interface adheres to semantic versioning and versions with the same major version number are binary and backward compatible, but the underlying TDLib API can be different for different minor and even patch versions. If you need to support different TDLib versions, then you can use a value of the version option to find exact TDLib version to use appropriate API methods.

See example/python/tdjson_example.py for an example of such usage.

TDLib is licensed under the terms of the Boost Software License. See LICENSE_1_0.txt for more information.