Now in private beta — Request access
Stesura

A Web-based Word processor
that is
powered by ProseMirror 

Drop in as a component, extend and ship a word processor in your app.

This document is all json.

For those who need a word processor in their app with a modern API and flexibility to match their value proposition.

Keep control of your data and your users on your app. Focus on building what makes your app special, don't spend months building a word clone.

And everything else to extend it and make it a pillar of your app.

A basic word processor is not enough. You want a modern, flexible one whose API conforms to your app.

The whole ProseMirror API

Write plugins, change the schema, add your own nodes and marks, hook the transaction pipeline. Not a configuration object — the actual editor.

React inside the editor

NodeViews are real React components in your tree, with your context and your state. No portals, no second subtree.

Editable on the server

Dispatch transactions from your backend while clients collaborate on the same document. Same schema, same validation as a keystroke.

Collaboration you host

Real-time editing on your own servers, against your own database. Documents never transit anyone else's infrastructure, including ours.

Runs on the client

A React component that does its work in the browser. No editing service to keep up, no per-document round trip.

* Proofreading, collaboration and PDF export are the exceptions as they run server-side.

A JSON document model

The document is a typed JSON tree, not an opaque blob. Diff it, validate it, generate it, and store it wherever the rest of your data lives.

Real HTML, not a canvas

The document is the DOM. Screen readers and browser tools see real elements — no pixel buffer to reimplement a11y against.

Your chrome, not ours

Build your own toolbar, menus, popovers, hover cards — whatever the rest of the app already uses. The editor does not own the chrome.

Your CSS

Theme it with the tokens you already have. No iframe, no sealed skin, no second design system to maintain.

What sets us apart

A full document stack, one package at a time.

Start free with the editor foundation. Add the premium packages — pagination, review, references, PDF, AI — as you need them.

A complete core. Premium add-ons.

Stesura is in private beta. The split below is how we plan to license it; during the beta, access to every package is by agreement.

Coreplanned free tier

The full editor foundation, in a continuous-flow layout.

The entire schema, commands, and UI elements
Stylesheets, legal numbering & advanced formatting
DOCX, Markdown & JSON import and export
Track changes & threaded comments
Real-time collaboration (self-hosted)
Premium add-onslicensed

Bolt on as your product grows.

Pagination — sections, headers & footers, line numbers
Paginated PDF export
References — footnotes, endnotes, cross-references, TOC
Proofreading & document compare
AI — autocomplete, document chat & text actions
For your clients' users

Your clients deserve a real text editor.

The people inside your product open documents all day. Give them the desktop word processor they already know — in the browser, with nothing to install.

Familiar, accessible, and faithful to the page. In Chrome and Edge, the PDF your client signs has the pages they saw on screen; other browsers are best effort.

Familiar from day one

The Word-like surface your users already know — no training, no migration.

Nothing to install

Runs in any modern browser, on any OS — Chromebook and Linux included.

Built for accessibility

Keyboard-first and screen-reader aware, built on real HTML semantics.

Documents they can trust

True pages, legal numbering, and footnotes, with a PDF that keeps the page breaks they saw.

Frequently asked questions

Are you going to do a non-React version?

Can I use the packages server-side?

Can I use this with Yjs for collab?

What happens if I downgrade from the premium packages to the free ones?

What about security?

Is it extensible?

Put a real word processor in your product.

Stesura is in private beta. Book a demo and we'll get you set up.

Want to know why we built this? Read the story.