@hashgraph/sdk

Hiero JavaScript SDK

The JavaScript SDK for interacting with a Hiero based network

[!NOTE]
The project has been transferred from the https://github.com/hashgraph org and therefore the namespace is at several locations still based on hashgraph and hedera. We are working actively on migrating the namespace fully to hiero.

Install

NOTE: v1 of the SDK is deprecated and support will be discontinued after October 2021. Please install the latest version 2.x or migrate from v1 to the latest 2.x version. You can reference the migration documentation.

# with NPM
$ npm install --save @hiero-ledger/sdk

# with Yarn
$ yarn add @hiero-ledger/sdk

# with PNPM
$ pnpm add @hiero-ledger/sdk

Browser Usage

The SDK is also available as a UMD (Universal Module Definition) build, which can be loaded directly in the browser from popular CDNs:

UNPKG

<script src="https://unpkg.com/@hiero-ledger/sdk@2.70.0/dist/umd.js"></script>

When using the UMD build in the browser, the SDK will be available as a global variable sdk. A minified version is also available at dist/umd.min.js.

Build

Prerequisites

• Taskfile tool installation
• Node.js: It is recommended to use Node.js v20 or higher for best performance and compatibility. The package may also work with Node.js v16, but this version has not been officially tested.

# with npm
$ npm install -g @go-task/cli

# with homebrew
$ brew install go-task

• pNpm package manager installation

# with npm
$ npm install -g pnpm

# with homebrew
$ brew install pnpm

Windows

[!Note] Long paths must be enabled. Link to official documentation: Windows-Long-Path

Git must support long paths

LF line endings must be enforced.

After downloading the repo run:

• task install

• task build to build the SDK

Development

Local Development Workflow

The SDK uses pnpm workspaces to manage its monorepo structure with sub-packages (@hiero-ledger/proto and @hiero-ledger/cryptography). For local development and testing the SDK in other projects, use the following workflow:

Build and Link Globally

Build the SDK and link it globally for use in other local projects:

task build:dev

This command:

• Builds all packages (proto, cryptography, and the main SDK)
• Creates global symlinks for all three packages
• Allows you to use the local SDK in any other project on your machine

Use in Another Project

In your other project, link to the globally linked SDK:

cd /path/to/your/other/project
pnpm link --global @hiero-ledger/sdk

Now any changes you make to the SDK and rebuild will be immediately available in your project.

Unlink and Clean

When you're done with local development:

# In the hiero-sdk-js repository
task clean

This removes all global links and cleans up node_modules.

To unlink in your other project:

# In your other project
pnpm unlink @hiero-ledger/sdk
pnpm install

React Native Support

The Hiero JavaScript SDK provides comprehensive support for React Native environments, including Expo. To ensure seamless integration, follow the guidelines based on your Expo version:

✅ Hiero Javascript SDK Version 2.60 and Above For projects using SDK version 2.60 and above, Expo SDK version 51+ is supported, the SDK requires the react-native-get-random-values package in order to work. To install it, run:

npm install react-native-get-random-values

After installation, the native dependency must be linked for the respective platforms:

🔗 Linking for Native Platforms

• iOS: Run the following command to install the native modules:

cd ios && pod install

Then, rebuild the iOS project.

• Android: Rebuild the Android project to link the dependency

⚠️ ✅ Hiero Javascript SDK Version 2.59 and Below For projects using SDK version 2.59 and below, Expo SDK Version 49 and below is supported, keep in mind that the SDK uses some functionalities provided from ethers/ethersproject and there is an issue using parts of ethers.js in this environment. A shims package has to be installed and imported before importing the SDK in your project.

• Useful information: here and here

npm install @ethersproject/shims

Import it before importing the SDK as shown below:

import '@ethersproject/shims';

import {
    Client,
    PrivateKey
    AccountBalance,
} from "@hiero-ledger/sdk";
...

The Hiero JavaScript SDK does not currently support the following:

• React Native Bare

Usage

See examples.

Every example can be executed using the following command from the root directory: node examples/[name-of-example].js.

Note: Before running any examples, ensure you have:

• Built the SDK by running task build in the root directory.
• Installed dependencies by running pnpm install in the examples directory

Configuration

For detailed information on configuring the SDK, including environment variables and client settings, please refer to the CONFIGURATION.md file.

Local Development Setup

For contributors and developers who want to run integration tests locally, we provide Solo - the official Hiero local network solution. Solo provides a production-like Kubernetes-based environment with consensus nodes and mirror node services.

Platform Requirements: Solo can only run on macOS or Linux. Windows users must use WSL2.

RAM Requirements:

• Single node setup: Minimum 12 GB RAM
• Dual node setup: Minimum 24 GB RAM (required for dynamic address book tests)

For complete system requirements, see the official Solo documentation.

Quick Setup

• Install dependencies:

  task install
  

• Run Solo setup (cluster + services):

  # Single node setup (default, requires 12 GB RAM)
  task solo:setup
  
  # Dual node setup (requires 24 GB RAM, needed for DAB tests)
  task solo:setup -- --num-nodes 2
  

  solo:setup is the only command that accepts initial version/build arguments:

  task solo:setup -- --consensus-node-version v0.70.0
  task solo:setup -- --mirror-node-version v0.146.0
  task solo:setup -- --consensus-node-version v0.70.0 --mirror-node-version v0.146.0
  task solo:setup -- --local-build-path ../hiero-consensus-node/hedera-node/data
  

  Typical timing:

  • First setup: ~10 minutes (image pulls + deployment)
  • Resume after pause: ~4 minutes

• (Required for dynamic address book tests) Configure hosts:

  Before running dynamic address book tests with dual-node setup, add Kubernetes service names to your /etc/hosts file:

  echo "127.0.0.1 network-node1-svc.solo.svc.cluster.local" | sudo tee -a /etc/hosts
  echo "127.0.0.1 envoy-proxy-node1-svc.solo.svc.cluster.local" | sudo tee -a /etc/hosts
  echo "127.0.0.1 network-node2-svc.solo.svc.cluster.local" | sudo tee -a /etc/hosts
  echo "127.0.0.1 envoy-proxy-node2-svc.solo.svc.cluster.local" | sudo tee -a /etc/hosts
  

  Note: This is only required for dynamic address book tests with dual-node setup. Skip if you're running single-node or other integration tests.

• Run integration tests:

  task test:integration
  

• Pause or fully tear down when done:

  # Pause: destroys mirror node, stops consensus node, stops cluster
  task solo:pause
  
  # Complete teardown: removes everything
  task solo:teardown
  

Daily Development Workflow

After initial setup, use this workflow for day-to-day development:

# Morning - Resume services (~4 minutes)
task solo:resume

# Work on your code and run tests
task test:integration

# End of day - Pause services
task solo:pause

For detailed setup instructions, troubleshooting, and advanced usage, see the Solo Setup Guide.

Prerequisites

Before setting up Solo, ensure you have:

• Docker Desktop (or Docker Engine)
• Kind (Kubernetes in Docker)
• kubectl
• Node.js v18+ (comes with npm/npx)

See the Solo Setup Guide for installation instructions.

Running Tests

Unit Tests

Unit tests do not require a local network and can be run directly:

task test:unit

Or separately for Node.js and browser:

task test:unit:node
task test:unit:browser

Integration Tests

Integration tests require a running local network. After setting up Solo (see above):

# Run all integration tests
task test:integration

# Run Node.js integration tests only
task test:integration:node

# Run browser integration tests only
task test:integration:browser

# Run dual-mode tests
task test:integration:dual-mode

Running Dynamic Address Book Tests

Dynamic address book (DAB) tests require:

• Dual-node setup: Run task solo:setup -- --num-nodes 2 (requires 24 GB RAM)
• /etc/hosts configuration: See step 4 in the setup section above

These tests validate that the SDK can correctly handle node address changes and reconnections using Kubernetes service names.

Note: All integration tests should pass reliably with the Solo setup. If you encounter failures:

• Verify Solo services are running: task solo:status
• For dynamic address book test failures, ensure you're using dual-node setup and /etc/hosts is configured
• Check the troubleshooting section in the Solo Setup Guide
• Try a complete reset: task solo:teardown && task solo:setup

Contributing

Whether you’re fixing bugs, enhancing features, or improving documentation, your contributions are important — let’s build something great together! Please read our contributing guide to see how you can get involved.

Code of Conduct

Hiero uses the Linux Foundation Decentralised Trust Code of Conduct.

License

Apache License 2.0