How To
Text Editing

Text Editing

Reflect supports high-quality collaborative text editing via the popular Yjs (opens in a new tab) library. All editors and tools built on Yjs are supported, including CodeMirror (opens in a new tab), Monaco (opens in a new tab), TipTap (opens in a new tab), Quill (opens in a new tab), and many others.

When running on Reflect, Yjs gets some extra powers too. For example, you can easily add server-side validation to your Yjs docs with Reflect's mutators.

Get Started

These steps assume you already have a project with Reflect setup. To quickly create one see Scaffold a New Project.


npm install yjs reflect-yjs

Instantiate Reflect

Create a Reflect instance as normal, but add the Yjs-specific mutators from reflect-yjs to your own:

import { Reflect } from "@rocicorp/reflect";
import { Provider, mutators as yjsMutators } from "reflect-yjs";
import * as Y from "yjs";
import {mutators} from "./my-mutators.ts"
const r = new  Reflect({
  mutators: {

Register Yjs mutators with your Reflect server

Just like your own mutators, the mutators from reflect-yjs run on both the client and server.

import { mutators } from "../my-mutators.ts";
import { mutators as yjsMutators } from "reflect-yjs";
export default function makeOptions() {
  return {
    mutators: {

Create a Yjs document and bind it to Reflect

The Provider from reflect-yjs sends Yjs changes to and from the server using Reflect.

const yDoc = new Y.Doc();
const yProvider = new Provider(r, "mydoc", yDoc);

Use Yjs

At this point, Yjs is ready to go. You can use it directly, but more likely you will connect it to some text editor. For example to use it with TipTap (opens in a new tab), first install the TipTap libraries:

npm add @tiptap/react @tiptap/extension-document @tiptap/extension-paragraph \
  @tiptap/extension-text @tiptap/extension-collaboration

Then create a TipTap editor and bind it to Yjs:

// ...
import Document from "@tiptap/extension-document";
import Paragraph from "@tiptap/extension-paragraph";
import Text from "@tiptap/extension-text";
import Collaboration from "@tiptap/extension-collaboration";
import { EditorContent, useEditor } from "@tiptap/react";
// ...
function App() {
  const editor = useEditor({
    extensions: [
        document: yDoc,
  // Render app.
  return (
      Type something:
          display: "flex",
          flexDirection: "column",
          alignItems: "stretch",
          width: 500,
          border: "1px solid black",

For a complete working example of the TipTap editor on Reflect, see Type. For examples using other editors, see the GitHub repo (opens in a new tab).

You can also consult the documentation for Yjs (opens in a new tab) itself.


You can apply server-side validation to Yjs documents, just like other Reflect data. In your Reflect server, override the default updateYJS mutator to provide a validator:

import {regex} from 'badwords-list';
function makeOptions() {
  return {
    mutators: {
      updateYJS: updateYJS({
        validator: doc => {
          const text = doc.getText('monaco');
          const string = text.toString();
          let match: RegExpExecArray | null = null;
          while ((match = regex.exec(string)) !== null) {
            const badWordLength = match[0].length;
            text.delete(match.index, badWordLength);
            text.insert(match.index, '*'.repeat(badWordLength));

Not seeing what you're looking for? We're planning to improve the Yjs server-side API. Find us on Discord (opens in a new tab) to let us know what you're missing.


YJs documents are limited to 1MB. This is not a fundamental limit, but a function of some details of our messaging infrastructure. If this is a problem for you let us know, it can be fixed.