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Inlyne

Real-time collaborative markdown platform with web + VS Code sync.

Inlyne is a real-time collaborative markdown editing platform that enables multiple users to simultaneously edit and synchronize documents across both web applications and a custom VS Code extension.

The system integrates a Java (Spring Boot) backend, PostgreSQL persistence, and WebSocket/STOMP messaging to maintain live document state consistency across concurrent collaborators.

Overview

Inlyne was built to explore the challenges of real-time collaborative systems, including:

  • Concurrent editing
  • State synchronization
  • Event-driven communication
  • Cross-client consistency
  • The platform supports collaborative markdown editing in the browser and integrates directly into VS Code via an extension, allowing developers to work inside their local environments while syncing changes live.

    System Architecture

    Frontend

  • Web-based markdown editor
  • Client-side state management
  • WebSocket integration for live updates
  • Backend

  • Java (Spring Boot) REST API
  • WebSocket/STOMP messaging layer
  • PostgreSQL for document persistence
  • Communication

  • REST APIs for document management
  • WebSockets for live edit propagation
  • Event-based messaging for concurrency handling
  • Real-Time Synchronization

    Inlyne maintains consistent document state across connected clients using WebSockets and STOMP messaging.

    When a user edits a document:

    1. The change is emitted over a WebSocket connection.

    2. The backend processes and broadcasts the update.

    3. Other connected clients receive and apply the update in real time.

    The system required careful handling of:

  • Concurrent edit ordering
  • State reconciliation
  • Temporary desynchronization scenarios
  • Frontend/backend consistency issues
  • Debugging synchronization errors exposed common distributed-system challenges such as race conditions and message ordering conflicts.

    VS Code Extension

    Inlyne includes a custom VS Code extension that connects to the backend through the same WebSocket-based protocol.

    This enables:

  • Live document synchronization inside VS Code
  • Cross-environment editing (browser to local IDE)
  • Shared state updates between multiple collaborators
  • The extension demonstrates integration between backend APIs and developer tooling environments.