Second Brain 🧠 - Your AI-Powered Knowledge Vault.

Never lose an important link again - Store, organize and instantly retrieve your saved content from Twitter, YouTube, Reddit and more using intelligent embeddings.

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✨ Key Features

Second Brain is an intelligent knowledge management platform that helps you store, organize, and retrieve important content from various platforms using AI-powered embeddings. Think of it as your external memory bank for digital content.

📂 Project Repositories

This project is split into two repositories for better separation of concerns:

🖥️ Frontend (Client)

https://github.com/Acid-OP/second-brain-frontend

###⚙️ Backend (Server)

https://github.com/Acid-OP/second-brain-backend

🌟 Key Features

🗄️ Smart Content Storage

• Save important links from multiple platforms:
  • Twitter/X posts
  • YouTube videos
  • Reddit threads
  • General web links
• Store content with rich metadata:
  • Custom titles
  • Descriptions
  • Content type classification
  • AI-generated embeddings for powerful search

🔍 Intelligent Search

• Find your saved content effortlessly:
  • Search by title, description, or content characteristics
  • Uses open-source embedding models (not commercial LLMs)
  • Note: While highly effective, results may vary occasionally due to the nature of open-source models

💠 Vector Search Powered by ChromaDB

• Lightning-fast semantic search using ChromaDB vector database
• Persistent storage for your embeddings
• Automatic index management

🧠 Share Your Brain

• Create shareable versions of your knowledge repository:
  • Generate public links to showcase your collections
  • Toggle privacy settings to make collections private
  • Control exactly what others can see

🛠️ Content Management

• Full CRUD functionality:
  • Create new knowledge cards
  • Share your cards.
  • Delete content you no longer need
  • Organize your knowledge base

🔒 Secure Access

• Complete user authentication:
  • Secure signup/login
  • Protected content storage
  • Logout functionality

🚀 Getting Started

Prerequisites

• Node.js (v16 or higher)
• npm or yarn package manager
• MongoDB Atlas account (for database storage)
• Embedding API Key (choose one of these options):
  • Preferred: Any LLM API key (OpenAI, Hugging Face, etc.)
  • Alternative: We've pre-configured support for the open-source sentence-transformers/all-MiniLM-L6-v2 model
• ChromaDB (either local or cloud instance)
  • Local: pip install chromadb (Python 3.7+ required)
  • Cloud: Free tier available at Chroma Cloud

About Our Model Choice:

We default to using the open-source all-MiniLM-L6-v2 sentence transformer because:

• 🆓 No API costs or usage limits
• 🔒 Runs completely locally (no data sent externally)
• ⚖️ Balanced 384-dimensional embeddings
• 📏 Good performance for semantic search tasks

For better results, you can optionally configure:

1. OpenAI embeddings (requires API key)
2. Hugging Face inference API
3. Any other compatible embedding service

Installation

1. Clone the repository:

   git clone https://github.com/your-username/second-brain.git
   cd second-brain

2. Install dependencies:

   npm install

3. Environment Variables Setup

Create these .env files in their respective directories:

For Local Development:

# Frontend (create in /Client/.env)
VITE_BACKEND_URL=http://localhost:5000 # or Vercel deployed Backend URL

# Backend (create in /Server/.env)
MONGO_URI=your_mongodb_atlas_connection_string
JWT_SECRET=your_secure_random_string
PORT=YOUR PORT
FRONTEND_URL=http://localhost:3000 # or Vercel deployed Frontend URL
EMBEDDING_MODEL=all-MiniLM-L6-v2  # or 'openai' for OpenAI
# OPENAI_API_KEY=sk-your-key-here  # Uncomment if using OpenAI
# ChromaDB Configuration 
CHROMA_DB_URL=http://localhost:8000  # For local ChromaDB
# OR for Chroma Cloud:
# CHROMA_DB_URL=https://your-cluster-id.chroma.cloud

4. Run the development server:
   ```bash
   npm run dev

🧩 How It Works

Saving Content

1. Navigate to the "Add Content" section
2. Enter:
   • Title (what you'll remember it by)
   • URL (the original content link)
   • Description (key points to remember)
   • Content type (YouTube, Twitter, Reddit, or General)
3. The system automatically generates AI embeddings for powerful search

Finding Content

1. Use the search functionality
2. Enter any details you remember:
   • Exact title or description words
   • Related concepts or topics
   • Content characteristics
3. The system will surface the most relevant matches

Sharing Collections

1. Go to "Share Brain" section
2. Select a collection to share
3. Click "Share" (By default it is Private):
   • Public: Anyone with link can view
   • Private: Only you can access
4. Copy the shareable link to distribute
5. Click on "Make it Private" to stop the Share functionality

🛡️ Privacy & Security

• Your data is stored securely in MongoDB Atlas
• Authentication uses JWT tokens
• Passwords are hashed before storage
• You maintain full control over shared content

🌐 Technologies Used

Frontend

• React.js
• TypeScript
• Tailwind CSS
• Framer Motion (animations)
• Axios (API calls)

Backend

• Node.js
• TypeScript
• Express.js
• Auth(JWT, ZOD)
• MongoDB (database)
• Mongoose (ODM)

AI Components

• Open source model for embeddings generation.
• Custom similarity search algorithms

🤝 Contributing

We welcome contributions! Please follow these steps:

1. Fork the project
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

📜 License

Distributed under the MIT License. See LICENSE for more information.

📧 Contact

For questions or support, contact us at:

• Email: gauravkapur596@gmail.com
• Twitter: https://x.com/GauravKapurr

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Second Brain - Never lose an important idea or resource again. Your digital memory, enhanced with AI.