Real-Time Collaborative Code Editor
A browser-based collaborative editor built for pair programming, guided coding sessions, and remote technical interviews.
A stronger hero that frames this project like a real case study instead of a plain information page.
Impact
Overview
The project was designed to make remote coding feel closer to sitting beside another developer. Instead of treating collaboration as simple text syncing, the experience combines live editing, room-based access control, remote cursor awareness, and communication tools in a single workflow.
Users can create private rooms, approve or reject access requests, and work together on the same codebase with synchronized updates. The goal was to support both structured collaboration, such as mentoring and interview practice, and spontaneous shared problem-solving sessions.
Problem
Most browser-based collaboration tools either focus on communication without a strong editing experience, or focus on editing while leaving access control and session coordination as an afterthought.
I wanted to build a space where users could share code in real time, manage who joins a room, and communicate without constantly switching between multiple apps and tabs.
Key Features
- Private coding rooms with admin-controlled access requests
- Real-time multi-user code synchronization
- Remote cursor presence for shared awareness
- Multi-language editing with Monaco Editor
- Folder upload support for working with project files
- Integrated peer-to-peer audio and video using WebRTC
Timeline
Defined the collaboration flow, room access model, and main editing scenarios.
Integrated Monaco Editor and established the synchronized editing foundation.
Added Socket.IO rooms, presence events, cursor syncing, and signaling.
Connected WebRTC audio/video on top of the shared coding session.
Published the production app with PM2, Nginx, HTTPS, and Oracle Cloud.
User Workflow
- A user creates a private room and becomes the room admin.
- Other users request access before joining the shared coding session.
- Once approved, participants receive the current editor state and begin sending incremental changes over Socket.IO.
- Cursor positions, presence events, and signaling data are broadcast separately to keep the collaboration experience responsive and organized.
- For voice and video, peers establish direct WebRTC connections after exchanging signaling messages through the server.
Architecture
- The client application handles room UI, editor rendering, presence indicators, and local edit buffering.
- The real-time layer uses Socket.IO rooms to scope document events, access requests, and user-presence updates.
- The synchronization logic applies a lightweight Operational Transform strategy so incoming edits can be merged safely even when multiple users type at nearly the same time.
- The communication layer uses WebRTC for peer-to-peer media streams while relying on Socket.IO only for signaling.
Technical Focus
- Implemented a lightweight Operational Transform strategy to keep concurrent edits consistent across connected users.
- Used Socket.IO for low-latency event delivery, room coordination, presence updates, and WebRTC signaling.
- Embedded Monaco Editor to provide a familiar IDE-like editing experience directly in the browser.
- Deployed the application in production using PM2, Nginx, HTTPS, and Oracle Cloud infrastructure.
Challenges Solved
- Handling simultaneous edits from multiple users without introducing broken cursor positions or inconsistent document state.
- Balancing collaboration features with a clean, responsive browser editing experience.
- Coordinating real-time editor events and peer connection signaling within the same application flow.
Deployment
- The app was deployed to Oracle Cloud with Nginx acting as the reverse proxy and HTTPS termination layer.
- PM2 was used to run and manage the Node.js process in production.
- Let's Encrypt certificates were configured to secure both the application and the signaling workflow over HTTPS.
Outcome
The final result is a portfolio project that demonstrates real-time systems thinking, practical collaboration UX, and production deployment knowledge in one product.
It also reflects a strong engineering focus on concurrency handling, event-driven architecture, and creating interactive browser experiences beyond standard CRUD interfaces.