GitLyser

GitHub Profile Analyzer - Comprehensive analysis tool for GitHub users and organizations with advanced visualizations, repository insights, code quality metrics, and collaboration analytics.

📸 Screenshots

Main GitLyser dashboard with key profile analytics

Detailed repository cards with summaries and metrics

Contribution heatmap and activity timeline visualizations

Code quality metrics and pull request analytics dashboard

🚀 Quick Start

1. Install Dependencies

npm install

2. Setup GitHub Token (Optional but Recommended)

Get Your Token:

1. Go to GitHub Settings → Developer settings → Personal access tokens
2. Click "Generate new token" → "Generate new token (classic)"
3. Name: GitLyser
4. Expiration: Choose your preference
5. Scopes: Select public_repo (read-only)
6. Click "Generate token" and copy it immediately

Where to Add:

Local Development:

• Create .env.local file in the project root
• Add: GITHUB_TOKEN=your_token_here

Production (Vercel):

• Go to Vercel Dashboard → Your Project → Settings → Environment Variables
• Add GITHUB_TOKEN with your token value
• Select environments: Production, Preview, Development
• Redeploy your application

Why? Increases rate limits from 60/hour (unauthenticated) to 5,000/hour (authenticated). FREE - no charges.

3. Setup OpenAI Key (Optional - For Smart Summary)

Get Your Key:

1. Go to OpenAI Platform → API Keys
2. Click "Create new secret key"
3. Name it and copy the key

Where to Add:

• Click the "Smart Summary" button in the app header (top-right on desktop and mobile)
• Enter your OpenAI API key in the modal
• Click "Save Settings"
• Key is stored securely in your browser's local storage (never sent to our servers)

Why? Enables AI-powered repository summaries. Subject to OpenAI's pricing.

4. Run Development Server

npm run dev

Open http://localhost:3000 to start analyzing profiles.

✨ Features

Profile Analysis

• Analyze any GitHub user or organization with profile overview, stats, and search functionality
• Sticky header keeps profile info visible while scrolling
• Fully responsive design for desktop, tablet, and mobile

Data Visualizations

• Language Distribution - Interactive pie chart of programming languages
• Language Usage - Bar chart with detailed statistics and percentages
• Repository Size Distribution - Visual breakdown of repository sizes
• Contribution Heatmap - GitHub-style contribution calendar with year selection
• Activity Timeline - Chronological timeline of commits, PRs, issues, repos, and stars with filtering

Repository Insights

• Expandable repository cards with comprehensive details
• Heuristic-based summaries from README, dependencies, and file structure
• Smart Summary - AI-powered summaries using OpenAI GPT-4o-mini (optional, requires API key)
• Automatic tech stack detection from README, package files, and file structure
• Language statistics, topics, and tags

Repository Details

• Project overview with AI-powered summaries
• Tech stack detection and detected features (tests, docs, CI/CD, Docker, config files)
• Documentation highlights (README excerpts, CONTRIBUTING.md, CHANGELOG.md, etc.)
• Basic information, timeline, settings, statistics, and clone URLs
• Pull requests grouped by base branch with recent activity

Pull Request Analytics

• PR metrics dashboard with total PRs, success rate, and average review time
• Active reviewers list (top 10) and PR size distribution (Small/Medium/Large)
• Analyzes up to 50 most recent PRs with IQR outlier filtering
• PRs grouped by base branch with recent activity

Repository Health Score

• 0-100 health score with visual indicators and color-coded status
• Score breakdown across 5 categories: Documentation, Maintenance, Community, Resolution Time, Code Quality
• Improvement recommendations based on score analysis

Code Quality Metrics

• Average PR review time with outlier filtering (analyzes up to 50 PRs)
• Average code churn per commit (analyzes up to 100 commits, excludes merge commits)
• Dependency health tracking from package files
• Code churn trends visualization over last 30 days
• Quality recommendations and interactive charts

Comparison View

• Compare up to 3 GitHub profiles side-by-side
• Compare metrics, languages, and activity across profiles
• AI-powered comparison insights using GPT-4o-mini (optional, requires API key)
• Supports overall, technical skills, and role match comparisons

Additional Features

• Metrics Info Modal - Detailed explanations of all calculations (click "Info" button)
• Mobile-Optimized - Bottom sheet layout for mobile devices
• Accessible UI - ARIA labels, keyboard navigation, semantic HTML
• Loading states, error handling, and one-click copy functionality

🔒 Security

• GitHub Token: Stored server-side only, never exposed to client
• OpenAI Key: Stored in browser localStorage, never sent to our servers
• Input Validation: All inputs sanitized to prevent injection attacks
• Error Sanitization: Tokens never appear in error messages
• Security Headers: Production-grade security headers enabled
• Graceful Degradation: App works without tokens (with lower rate limits)

🛠️ Tech Stack

• Next.js 16 - React framework with App Router
• Next.js API Routes - Serverless API endpoints
• TypeScript - Type safety
• Tailwind CSS 4 - Modern styling
• GitHub REST API - Profile, repository, and PR data
• GitHub GraphQL API - Contribution calendar data
• OpenAI API - AI summaries and comparisons (optional)
• Recharts - Interactive charts and visualizations
• React Markdown - Markdown rendering for READMEs