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+# What is VaultLink?
+
+VaultLink is a self-hosted real-time synchronization system for Obsidian vaults. It provides collaborative file syncing with automatic conflict resolution, designed for users who want complete control over their data.
+
+## Overview
+
+VaultLink consists of three main components:
+
+### Sync Server
+
+A Rust-based WebSocket server that handles:
+- Real-time bidirectional synchronization
+- Document versioning with SQLite
+- User authentication and vault access control
+- Operational transformation for conflict resolution
+
+### Obsidian Plugin
+
+A native Obsidian plugin that:
+- Integrates sync directly into your Obsidian workflow
+- Provides real-time updates as you edit
+- Handles file watching and automatic synchronization
+- Works across desktop and mobile platforms
+
+### CLI Client
+
+A standalone synchronization client that:
+- Syncs vaults without requiring Obsidian
+- Perfect for servers, automation, or backup systems
+- Provides file watching and bidirectional sync
+- Runs in Docker or as a standalone binary
+
+## Key Features
+
+### Real-Time Synchronization
+
+Changes are synchronized immediately via WebSocket connections. When multiple users edit the same file, operational transformation ensures all edits are preserved without conflicts.
+
+### Self-Hosted Architecture
+
+Run the sync server on your own infrastructure:
+- Full control over data storage and access
+- No dependency on third-party services
+- Configurable authentication and authorization
+- Deploy anywhere: cloud VPS, home server, or localhost
+
+### Operational Transformation
+
+VaultLink uses the `reconcile-text` library for intelligent conflict resolution:
+- Simultaneous edits are automatically merged
+- No manual conflict resolution required
+- Preserves intent of all contributors
+- Works seamlessly in the background
+
+### Flexible Authentication
+
+Configure user access per vault:
+- Token-based authentication
+- Per-user vault access control
+- Allow-list or deny-list patterns
+- Support for multiple users and vaults
+
+## Use Cases
+
+### Personal Sync
+
+Synchronize your Obsidian vault across multiple devices:
+- Laptop, desktop, and mobile in real-time
+- No cloud service subscription required
+- Full privacy and data control
+
+### Team Collaboration
+
+Share knowledge bases with teammates:
+- Real-time collaborative editing
+- Granular access control per vault
+- Self-hosted for enterprise security requirements
+
+### Automated Backups
+
+Use the CLI client for automated workflows:
+- Scheduled backups to remote servers
+- Integration with existing backup systems
+- Headless operation without Obsidian
+
+### Development & Testing
+
+Synchronize documentation across environments:
+- Keep docs in sync with development environments
+- Automated deployment of documentation
+- Version control integration
+
+## How It Works
+
+1. **Server Setup**: Deploy the sync server on your infrastructure
+2. **Authentication**: Configure users and vault access in `config.yml`
+3. **Client Connection**: Connect via Obsidian plugin or CLI client
+4. **Initial Sync**: Client uploads local files to server
+5. **Real-Time Updates**: Changes sync bidirectionally via WebSocket
+6. **Conflict Resolution**: Operational transformation handles simultaneous edits
+
+## Technology Stack
+
+- **Server**: Rust with Axum framework, SQLite database, WebSocket protocol
+- **Frontend**: TypeScript with WebSocket client, npm workspaces
+- **Sync Algorithm**: reconcile-text operational transformation library
+- **Deployment**: Docker images, binary releases, or source builds
+
+## Next Steps
+
+Ready to get started?
+
+- [Getting Started Guide →](/guide/getting-started)
+- [Server Setup →](/guide/server-setup)
+- [Architecture Overview →](/architecture/)