Get started - Get started with React and Redux

In this guide, you’ll learn how to use integrate Liveblocks into your React + Redux application. The @liveblocks/redux package provides a store enhancer to turn selected parts of your Redux store into a real‑time shared state between clients. This approach makes it easy to convert an existing non-collaborative application into one. It also enables you to keep your front-end architecture without sprinkling Liveblocks code all over your code base.

If you’re not using a state-management library, we recommend reading our dedicated React guide below:

You can also follow our step-by-step tutorial to learn how to use Liveblocks.

Install Liveblocks into your project

Create a new app with create-react-app and once the installation is complete, run the following command to install Liveblocks dependencies:

$npm install @liveblocks/client @liveblocks/redux redux react-redux @reduxjs/toolkit

Connect to Liveblocks

You’ll need an API key in order to use Liveblocks. Create a Liveblocks account to get your API key. It should start with pk_.

Then, create a client with createClient and set your public key as shown below.

import { createClient } from "@liveblocks/client";
const client = createClient({ publicApiKey: "pk_prod_xxxxxxxxxxxxxxxxxxxxxxxx",});

Setup your Liveblocks real‑time enhancer

Use our enhancer in your store setup and pass the client created previously as the configuration. This will add a new state called liveblocks to your store, enabling you to interact with our Presence and Storage APIs.

import { createClient } from "@liveblocks/client";import { enhancer } from "@liveblocks/redux";import { configureStore, createSlice } from "@reduxjs/toolkit";
const client = createClient({ publicApiKey: "pk_prod_xxxxxxxxxxxxxxxxxxxxxxxx",});
const initialState = {};
const slice = createSlice({ name: "state", initialState, reducers: { /* logic will be added here */ },});
function makeStore() { return configureStore({ reducer: slice.reducer, enhancers: [ enhancer({ client, }), ], });}
const store = makeStore();
export default store;

Then setup your redux store at the top of your React tree.

import React from "react";import ReactDOM from "react-dom";import "./index.css";import App from "./App";
import { Provider } from "react-redux";import store from "./store";
ReactDOM.render( <React.StrictMode> <Provider store={store}> <App /> </Provider> </React.StrictMode>, document.getElementById("root"));

Connect to a Liveblocks room

A room is the virtual space where people collaborate. To create a multiplayer experience, you’ll need to connect your users to a Liveblocks room.

Dispatch enterRoom to start syncing parts of your store to the Liveblocks room and dispatch leaveRoom to stop the synchronization. With React useEffect, you can automatically enter and leave a Liveblocks room as your component is mounting and unmounting.

import React, { useEffect } from "react";import { useDispatch } from "react-redux";import { actions } from "@liveblocks/redux";
import "./App.css";
export default function App() { const dispatch = useDispatch();
useEffect(() => { dispatch(actions.enterRoom("room-id"));
return () => { dispatch(actions.leaveRoom("room-id")); }; }, [dispatch]);
return <div className="container">To-do App</div>;}

Get other users in the room

If you want to list all the people connected to the room, you can use state.liveblocks.others to get an array of the other users in the room.

import { useSelector } from "react-redux";
function App() { const others = useSelector((state) => state.liveblocks.others);}

Update user presence

To create immersive multiplayer experiences, it’s helpful for each person in the room to share their real‑time state with other connected users. That real‑time state often corresponds to a cursor position or even the item a user has currently selected. We call this concept "Presence".

For instance, to share the cursor’s position in real‑time with others, we’re going to add a new presenceMapping option to our enhancer to specify which part of the state maps to the current user’s presence.

/* ... imports and client setup ... */
const initialState = { cursor: { x: 0, y: 0 },};
const slice = createSlice({ name: "state", initialState, reducers: { setCursor: (state, action) => { state.cursor = action.payload; }, },});
export const { setCursor } = slice.actions;
function makeStore() { return configureStore({ reducer: slice.reducer, enhancers: [ enhancer({ client, presenceMapping: { cursor: true }, }), ], });}
const store = makeStore();
export default store;

Then you can dispatch an action like in any redux app and we will broadcast this cursor to everyone in the room.

import { useDispatch } from "react-redux";import { setCursor } from "./store.js";
function YourComponent() { const dispatch = useDispatch();
return ( <div style={{ width: "100vw", height: "100vh" }} onPointerMove={(e) => dispatch(setCursor({ x: e.clientX, y: e.clientY }))} /> );}

Get other users’ presence

Get people’s cursor positions with => user.presence?.cursor). It’s worth noting that a user presence can be undefined.

import { useSelector } from "react-redux";
function OthersCursors() { const others = useSelector((state) => state.liveblocks.others);
const othersCursors = => user.presence?.cursor);
// Render cursors with custom SVGs based on x and y}

Sync and persist the state across client

As opposed to the presence, some collaborative features require that every user interacts with the same piece of state. For example, in Google Docs, it is the paragraphs, headings, images in the document. In Figma, it’s all the shapes that make your design. That’s what we call the room’s storage.

The room’s storage is a conflicts-free state that multiple users can edit at the same time. It is persisted to our backend even after everyone leaves the room. Liveblocks provides custom data structures inspired by CRDTs that can be nested to create the state that you want.

  • LiveObject - Similar to JavaScript object. If multiple users update the same property simultaneously, the last modification received by the Liveblocks servers is the winner.
  • LiveList - An ordered collection of items synchronized across clients. Even if multiple users add/remove/move elements simultaneously, LiveList will solve the conflicts to ensure everyone sees the same collection of items.
  • LiveMap - Similar to a JavaScript Map. If multiple users update the same property simultaneously, the last modification received by the Liveblocks servers is the winner.

When using our Redux integration you cannot interact directly with these data structures. Our enhancer synchronizes your store with our data structures based on the storageMapping configuration.

Here is an example to explain how it works under the hood. Imagine you have the following store:

/* ...client setup... */
const initialState = { firstName: "Marie", lastName: "Curie", discoveries: ["Polonium", "Radium"],};
const slice = createSlice({ name: "state", initialState, reducers: { setFirstName: (state, action) => { state.firstName = action.payload; }, setLastName: (state, action) => { state.lastName = action.payload; }, addDiscovery: (state, action) => { state.discoveries.push(action.payload); }, },});
export const { setScientist } = slice.actions;
function makeStore() { return configureStore({ reducer: slice.reducer, enhancers: [ enhancer({ client, storageMapping: { firstName: true, lastName: true, discoveries: true }, }), ], });}
const store = makeStore();

With this setup, the room's storage root is :

const root = new LiveObject({  firstName: "Marie",  lastName: "Curie",  discoveries: new LiveList(["Polonium", "Radium"]),});

If you update your store by dispatching setFirstName("Pierre"), the enhancer will do root.set("firstName", "Pierre") for you and update the store of all the users currently connected to the room. The enhancer compares the previous state and the new state to detect changes and patch our data structures accordingly.

The reverse process happens when receiving updates from other clients; the enhancer patches your immutable state.

When entering a room with enterRoom, the enhancer fetches the room's storage from our server and patches your store. If this is the first time you're entering a room, the storage will be empty. enterRoom takes an additional argument to initialize the room's storage.

enterRoom("room-id", {  firstName: "Lise",  lastName: "Meitner",  discoveries: ["Nuclear fission", "Protactinium"],});

Multiplayer undo/redo

Implementing undo/redo when multiple users can edit the app state simultaneously is quite complex!

When only one user can edit the app state, undo/redo acts like a "time machine"; undo/redo replaces the current app state with an app state that was already be seen by the user.

When multiple users are involved, undo or redo can lead to an app state that no one has seen before. For example, let's imagine a design tool with two users editing the same circle.

  • Initial state => { radius: "10px", color: "yellow" }
  • User A sets the color to blue => { radius: "10px", color: "blue" }
  • User B sets the radius to 20px => { radius: "20px", color: "blue" }
  • User A realizes that it prefered the circle in yellow and undoes its last modification => { radius: "20px", color: "yellow" }

A yellow circle with a radius of 20px in a completely new state. Undo/redo in a multiplayer app does not act like a "time machine"; it only undoes local operation.

The good news is that room.history.undo and room.history.redo takes that complexity out of your hands so you can focus on the core features of your app.

Access these two functions from the client like below so you can easily bind them to keyboard events (⌘+Z/⌘+⇧+Z on Mac and Ctrl+Z/Ctrl+Y on Windows) or undo and redo buttons in your application..

const { undo, redo } = client.getRoom("room-id").history;

Pause and resume history

Some applications require skipping intermediate states from the undo/redo history. Let's consider a design tool; when a user drags a rectangle, the intermediate rectangle positions should not be part of the undo/redo history. But they should be shared with the rest of the room to create a great experience.

room.history.pause and room.history.resume lets you skip these intermediate states. To go back to our design tool example, the sequence of calls would look like that:

  • User presses the rectangle
  • Call room.history.pause to skip future operations from the history
  • User drags the rectangle
  • User release the rectangle
  • Call room.history.resume

At this point, if the user calls room.history.undo, the rectangle will go back to its initial position.

const { pause, resume } = client.getRoom("room-id").history;

Next steps

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