Realtime Collaboration App

Multi-user app with live sync, presence and conflict handling.

Shape your prompt

9 fields

App namerequired

What do users collaborate on?required

Stack

Full-stack

Split

Server-rendered

Static

Language

Database

Realtime transport

Conflict strategy

Show presence / cursorsRequire tests

Your prompt

914 characters

The raw prompt, unchanged.

Still needed: App name, What do users collaborate on? — the preview updates as you type.

Output24 lines · 914 chars

You are a senior engineer specializing in realtime systems. Build a realtime collaboration app called "".

## What users collaborate on

## Tech
- Platform: Next.js (full-stack React)
- Language: TypeScript
- Database: PostgreSQL
- Transport: WebSockets

## Realtime requirements
- Conflict resolution: CRDT — explain how concurrent edits converge.
- Optimistic local updates with reconciliation on server confirmation.
- Reconnect gracefully and resync state after disconnects.
- Live presence: who's online and live cursors/selections.
- Handle late joiners receiving the current state correctly.
- Tests covering concurrent-edit and reconnect scenarios.

## Deliverables
1. Sync architecture and data model before coding.
2. The complete, runnable codebase (client + server).
3. README: setup, env vars, and how to test multi-user locally.

Make production-grade defaults and explain the consistency trade-offs.