Aider

Aider is AI pair programming in your terminal. It's a command-line tool that lets you pair program with LLMs to start new projects or build on existing codebases, providing a collaborative coding experience directly from your terminal.

Core Features

Key Capabilities

Intelligent Code Understanding

• Repository Mapping: Creates comprehensive maps of codebases for better context
• Multi-File Editing: Understands relationships between files and modules
• Language Agnostic: Works with Python, JavaScript, Rust, Go, C++, and 100+ languages
• Context Awareness: Maintains understanding of project structure and dependencies

Git Integration

• Automatic Commits: Every change is automatically committed with descriptive messages
• Change Tracking: Easy to diff, manage, and undo AI-generated changes
• Branch Management: Works seamlessly with existing git workflows
• History Preservation: Full audit trail of all AI-assisted modifications

Model Support

Installation & Setup

Quick Start

# Install aider
python -m pip install aider-install
aider-install

# Navigate to your project
cd /to/your/project

# Start with DeepSeek (recommended)
aider --model deepseek --api-key deepseek=<your-key>

# Or use Claude 3.7 Sonnet
aider --model sonnet --api-key anthropic=<your-key>

# Or use OpenAI o3-mini
aider --model o3-mini --api-key openai=<your-key>

Configuration Options

• API Keys: Support for multiple provider API keys
• Model Selection: Easy switching between different LLMs
• Repository Settings: Configure which files to include/exclude
• Git Configuration: Customize commit message formats

Advanced Features

IDE Integration

• Watch Mode: Monitor file changes and respond to comments in code
• Editor Agnostic: Works with any editor that can save files
• Live Collaboration: Real-time file watching and updates
• Comment-Driven: Add comments to request changes, aider implements them

Media & Context Support

• Image Support: Add images and screenshots for visual context
• Web Pages: Include web pages and documentation as context
• Voice Input: Speak requests using voice-to-code functionality
• URL Processing: Fetch and process web content for reference

Quality Assurance

• Automatic Linting: Runs linters after each change
• Test Integration: Executes tests and fixes failures automatically
• Error Handling: Detects and resolves compilation errors
• Code Validation: Ensures changes don't break existing functionality

Workflow Examples

Starting New Projects

# Create new directory and initialize
mkdir my-new-app
cd my-new-app
git init

# Start aider and begin development
aider
> Create a FastAPI web application with user authentication

Working with Existing Code

# Navigate to existing project
cd existing-project

# Start aider with specific files
aider app.py models.py

# Request changes
> Add error handling to the database connection logic
> Implement caching for the user profile endpoint

Testing and Bug Fixes

# Run aider with test files
aider src/ tests/

# Request comprehensive testing
> Add unit tests for all API endpoints
> Fix the failing test in test_authentication.py

Use Cases

Development Workflows

• Feature Development: Implement new features with AI assistance
• Bug Fixing: Diagnose and fix issues with intelligent analysis
• Refactoring: Modernize and improve existing code structure
• Documentation: Generate comprehensive code documentation

Learning and Exploration

• Code Review: Get explanations of complex code sections
• Best Practices: Learn modern development patterns and techniques
• New Technologies: Explore unfamiliar frameworks and libraries
• Debugging: Understand and resolve complex errors

Team Collaboration

• Code Consistency: Maintain style and patterns across projects
• Knowledge Transfer: Share expertise through AI-assisted development
• Onboarding: Help new team members understand existing codebases
• Standards Enforcement: Apply coding standards consistently

Performance Metrics

Usage Statistics

• GitHub Stars: 35,000+ stars
• Installations: 2.7M+ downloads
• Token Usage: 15B tokens processed weekly
• OpenRouter Ranking: Top 20 most used model
• Community: Active Discord and GitHub communities

Model Performance

Copy/Paste Mode

For users without API access, aider provides a streamlined copy/paste workflow:

# Generate prompts for web chat interfaces
aider --copy-paste

# Aider prepares context and instructions
# Copy to web chat (ChatGPT, Claude, etc.)
# Paste responses back to aider
# Changes applied automatically

Best Practices

Effective Usage

1. Start Small: Begin with simple changes and build complexity
2. Provide Context: Include relevant files and clear requirements
3. Use Git: Leverage automatic commits for change tracking
4. Test Frequently: Run tests after each significant change

Project Organization

• Clear Structure: Maintain well-organized project directories
• Documentation: Keep README and docs updated
• Testing: Include comprehensive test suites
• Dependencies: Use clear dependency management

Cost Management

• Model Selection: Choose appropriate models for task complexity
• Local Options: Use local models for privacy and cost savings
• Efficient Prompting: Write clear, specific requests
• Progress Tracking: Monitor token usage and API costs

Community Feedback

User Testimonials

• funkytaco: "This project is stellar."
• Starry Hope: "Aider has been revolutionary for me and my work."
• Matthew Berman: "The best AI coding assistant so far."
• koleok: "Been using aider as my daily driver for over a year ... I absolutely love the tool, like beyond words."

Key Benefits

• Terminal Native: Perfect for command-line focused developers
• Git Integration: Seamless version control workflow
• Model Flexibility: Not locked into single AI provider
• Privacy Options: Local model support for sensitive projects

Comparison with Alternatives

Advanced Configuration

Model Configuration

# Use specific models
aider --model claude-3-opus
aider --model gpt-4-turbo
aider --model deepseek-coder

# Local model setup
aider --model ollama/codellama
aider --model lmstudio/local-model

Repository Settings

# Include specific files
aider src/*.py tests/*.py

# Exclude directories
aider --exclude node_modules/ build/

# Add files dynamically
/add new_file.py
/drop old_file.py

Aider represents the command-line evolution of AI pair programming, offering developers a powerful, flexible, and git-integrated approach to AI-assisted development that works with any editor and respects existing workflows.