Casual Editor
Word-flavored web document editor·docs.casualoffice.org
Casual Editor is an open-source, real-time collaborative .docx editor that runs in the browser. It uses ProseMirror with an OOXML-preserving model, a React + Bun frontend, and a stateless Go WebSocket gateway implementing the y-websocket protocol for co-editing via Yjs. Document persistence is delegated to a pluggable host integration (an inline share-link implementation for v0, with WOPI/JWT-API support planned). Users can open a .docx file from their computer or start from a template, edit it collaboratively, and save it back as .docx.
What it's for
Features 12
- 14-template home gallery with real first-page PNG previews
- Open a file directly from your computer
- Open and save native .docx files in the browser
- Per-tag round-trip audit in CI
- Planned AI features: inline ask, rewrite panel, and DocOps chat panel
- Pluggable host integration (inline / WOPI / JWT-API behind a single Go interface)
- ProseMirror editor with an OOXML-preserving model
- Real-time multi-user co-editing via Yjs and y-prosemirror
- Stateless Go WebSocket gateway with no database or on-disk update log
- Templates across Personal, Work, Education, and Career categories
- Three-way fidelity harness comparing output vs LibreOffice and OnlyOffice DocumentBuilder
- Word-compat heuristics behind an opt-in flag (e.g. last-row closing border)
At a glance
Integrations
Pricing
Product is free and open source; JSON-LD offer lists price 0 USD, no paid plans stated.
Open-source and free; can be self-hosted via Docker or used as the hosted web demo.