Real-Time Collaborative Docs Platform

I am building a documentation platform and want to start with the heart of the product: real-time live-editing that lets multiple users work in the same document without collisions or noticeable lag.

Here is what I need right now
• A TypeScript-based collaboration engine that keeps every user’s cursor, selection and text in sync, even over spotty connections.
• Simultaneous editing out of the box, backed by a conflict-resolution approach you are comfortable with (OT, CRDTs, or a well-reasoned alternative).
• An in-document commenting system so teammates can discuss sections inline while edits are happening.

You are free to pick the precise stack, though a Node/Express or NestJS backend and a React front end would slot neatly into the rest of the codebase. Code quality matters: please include clear architecture decisions, unit tests around your sync logic, and concise setup instructions so I can drop the module into other TypeScript apps later.

Acceptance is simple: open two browser windows, type in both, watch everything stay perfectly in sync, leave a comment, refresh—nothing lost. If that works smoothly and the codebase is understandable, we are done and can move on to the next feature set.