Follow Diff

A privacy-first web application that allows you to see which Instagram users you follow who don't follow you back. This tool is designed with security in mind; all data processing happens directly in your browser. Your Instagram data is never uploaded to any server.

Overview

Follow Diff provides a simple and secure way to analyze your Instagram follower relationships using your official data export. By processing your followers.json and following.json files directly in the browser, this tool ensures that your data remains completely private and never leaves your computer.

The core comparison logic is implemented efficiently using a Set, which provides a time complexity of O(n + m), a significant improvement over a less optimal O(n*m) approach, ensuring a fast and responsive experience even with large datasets.

Live Demo

You can try out the application here: https://follow-diff.vercel.app/

How It Works

1. Request Your Data: First, you'll need to request your data from Instagram. A tutorial on how to do this is available on the application's website.
2. Upload Your Files: Once you have your followers.json and following.json files, you can drag and drop them into the application.
3. See the Difference: The application will then process the files and display a list of users who do not follow you back.

Key Features

• Client-Side Processing: All file processing and data analysis happen in the browser. No user data is ever sent to a server, guaranteeing privacy.

• Efficient Comparison Algorithm: Utilizes a JavaScript Set for fast and efficient comparison of follower and following lists.

• Robust Type-Safety: Employs TypeScript and Zod for schema validation to ensure the data from Instagram's export files is correctly parsed and handled, preventing runtime errors and improving maintainability.

• Comprehensive Testing: Includes a suite of tests using Jest and React Testing Library to ensure the reliability of core logic and UI components. The test suites achieve the following coverage:

  • Statements: 97.50%
  • Branches: 100.00%
  • Functions: 88.23%
  • Lines: 100.00%

Setup

To run this project locally:

1. Navigate to the project directory:

   cd follow-diff

2. Install dependencies:

   npm install

3. Run the development server:

   npm run dev

Tech Stack

Frontend

• React
• Next.js
• TypeScript
• TailwindCSS
• Zod (for schema validation)
• React-Dropzone (for file uploads)
• Jest & React Testing Library (for testing)
• Vercel (for deployment)

Backend

This project is a pure frontend application and does not have a backend.