Ever SDK
Core Client Library built on the EVER OS GraphQL API for Everscale DApp development
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Core Client Library is written in Rust that can be dynamically linked. It provides all heavy-computation components and functions, such as TON Virtual Machine, TON Transaction Executor, ABI-related functions, boc-related functions, crypto functions.
The decision to create the Rust library was made after a period of time using pure JavaScript to implement these use cases.
We ended up with very slow work of pure JavaScript and decided to move all this to Rust library and link it to Javascript as a compiled binary including a wasm module for browser applications.
Also this approach provided an opportunity to easily create bindings for any programming language and platform, thus, to make it possible to develop distributed applications (DApps) for any possible use-cases, such as: mobile DApps, web DApps, server-side DApps, enterprise DApp etc.
Client Library exposes all the functionality through a few of exported functions. All interaction with library is performed using JSON-RPC like protocol.
Library works over GraphQL API of EVER OS DApp Server. So, it can be used to interact directly with EVER OS Clouds.

Binding is a thin client library written on the specific language that acts like a bridge between a client library and an application code written on that language.

Supported platforms: Node.js, Web, React-Native for IOS/Android
Repository: JavaScript SDK

The simplest way is to use library in then Rust applications because of the native Rust library interface. The Rust interface is clear and well documented.
But what if you are required to use library in languages others than Rust?
You have some options:
  • use library module json_interface which provides access to library functions through JSON-RPC interface. This interface exports several extern "C" functions. So you can build a dynamic or static link library and link it to your application as any other external libraries. The JSON Interface is fully "C" compliant. You can find description in section JSON Interface.
  • use bindings already written by TON Labs and community. Below you can find a list of known bindings.
  • write your own binding to chosen language and share it with community.
If you choose using JSON Interface please read this document JSON Interface. Here you can find directions how to use json_interface and write your own binding.

Soft Breaking is API changes that include only new optional fields in the existing structures. This changes are fully backward compatible for JSON Interface.
But in Rust such changes can produce some problems with an old client code.
Look at the example below:
  1. 1.
    There is an API v1.0 function foo and the corresponding params structure:
struct ParamsOfFoo {
pub foo: String,
pub fn foo(params: ParamsOfFoo)
  1. 1.
    Application uses this function in this way:
foo(ParamsOfFoo {
foo: "foo".into(),
  1. 1.
    API v.1.1 introduces new field in ParamsOfFoo:
struct ParamsOfFoo {
pub foo: String,
pub bar: Option<String>,
From the perspective of JSON-interface it isn't breaking change because the new parameter is optional. But code snippet (2) will produce Rust compilation error.
  1. 1.
    To avoid such problems we recommend to use default implementation inside structure initialisation:
foo(ParamsOfFoo {
foo: "foo".into(),
For all Ton Client API structures Default trait is implemented.

The best way to build client libraries is to use build scripts from this repo.
Note: The scripts are written in JavaScript so you have to install Node.js (v.10 or newer) to run them. Also make sure you have the latest version of Rust installed.
To build a binary for a specific target (or binding), navigate to the relevant folder and run node build.js.
The resulting binaries are placed to bin folder in the gz-compressed format.
Note that the build script generates binaries compatible with the platform used to run the script. For example, if you run it on Mac OS, you get binaries targeted at Darwin (macOS) platform.
Note: You need latest version of rust. Upgrade it with rustup update command. Check version with rustc --version, it should be above or equal to 1.47.0.

Rebuild api.json:
cd toncli
cargo run api -o ../tools
Rebuild docs:
cd tools
npm i
node index docs -o ../docs
Rebuild modules.ts:
cd tools
npm i
node index binding -l ts -o ../../ever-sdk-js/packages/core/src

To run test suite use standard Rust test command
cargo test
SDK tests need EVER OS API endpoint to run on. Such an API is exposed by a DApp Server which runs in real networks and by local blockchain Evernode SE.
Evernode SE is used by default with address http://localhost and port 80. If you launch it on another port you need to specify it explicitly like this: http://localhost:port. If you have Evernode SE running on another address or you need to run tests on a real Everscale network use the following environment variables to override the default parameters
TON_USE_SE: true/false - flag defining if tests run against Evernode SE or a real network (DApp Server)
TON_NETWORK_ADDRESS - Dapp server or Evernode SE addresses separated by comma.
TON_GIVER_SECRET - Giver secret key. If not defined, default Evernode SE giver keys are used
TON_GIVER_ADDRESS - Address of the giver to use for prepaying accounts before deploying test contracts. If not defined, the address is calculated using `GiverV2.tvc` and configured public key

Instead of building library yourself, you can download the latest precompiled binaries from TON Labs SDK Binaries Store.
Download links
If you want an older version of library (e.g. 0.25.0 for macOS), you need to choose a link to your platform from the list above and replace 0 with a version: https://binaries.tonlabs.io/tonclient_0_25_0_darwin.gz
Downloaded archive is gzipped file
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Content Table
Useful links
What is Core Everscale Client Library
SDKs in other languages (bindings over Ever-SDK)
Official Javascript(Typescript) SDK
Community bindings
How to use library
How to avoid Soft Breaking Problems
Build client library
Build artifacts
Run tests
Download precompiled binaries