How To Integrate With a NodeJS Server

To get started, install the required connext package.

npm install @connext/client


  1. You need access to an Indra node.

Connext exposes 2 Indra nodes for public use:

  • Good for testing & experimenting on the Rinkeby test net

  • To interact with mainnet channels in production.

You can also run your own Indra node locally by running the start command in an indra repo.

git clone
cd indra
make start-headless

Once Indra wakes up after running the above, it’ll be available at http://localhost:8080 + a testnet eth provider will be available at http://localhost:8545 (you can send testnet ETH to any address by running bash ops/ 0xabc123... in the indra repo).

  1. You need access to an ethereum provider.

For small scale experiments, you can use a default ethers provider by passing in an optional first arg with the network name string (supported networks: “rinkeby” & “mainnet”).

In production, you’ll want to get an API key for alchemy, etherscan, or infura & use that URL.

  1. You need a key pair & you need to keep it safe.

Internally, we derive a signingAddress from a provided private key & funds at this Ethereum address will be used when calling deposit(). Alternatively, to protect the private key, you can wrap it in a ChannelSigner interface & inject that. See reference for more info.

  1. You need to consider where you’re going to store your state.

The simplest option is save it as a file. Alternatively, to increase performance you can save it to a postgres database. The @connext/store reference has more info about the options available.

Example Code

Create a state channel on a local testnet (Run make start-headless in indra first). Save channel state to a simple file.

import { connect } from "@connext/client";
import { getFileStore } from "@connext/store";
import { Wallet } from "ethers";

(async () => {

  const channel = await connect({
    ethProviderUrl: "http://localhost:8545",
    signer: Wallet.createRandom().privateKey,
    nodeUrl: "http://localhost:8080",
    store: getFileStore(),

  console.log(`Successfully connected channel with public id: ${channel.publicIdentifier}`);


Create a state channel on Rinkeby & save state to a postgres database.

import { connect } from "@connext/client";
import { getPostgresStore } from "@connext/store";
import { Wallet } from "ethers";

(async () => {

  const channel = await connect("rinkeby", {
    signer: Wallet.createRandom().privateKey,
    nodeUrl: "",
    store: getPostgresStore(`postgres://user:password@host:port/database`),

  console.log(`Successfully connected channel with public id: ${channel.publicIdentifier}`);


Reference Implementations


  • Coming soon to twitter account @TipDai

  • Browse the code at