- CPU Usage: Measure CPU usage during typical user interactions using browser developer tools or performance monitoring software. Lower usage indicates more energy-efficient code.
- Memory Consumption: Monitor memory usage throughout user sessions. Tools like Chrome DevTools' Memory panel can help identify memory-intensive code segments.

- Page Load Size: Analyze the size of resources (HTML, CSS, JavaScript, images) loaded during page loads. Browser developer tools or network analysis tools like Chrome DevTools or Firefox Network Monitor can provide insights.
- Number of HTTP Requests: Use browser developer tools or network analysis tools to count the number of requests made during page loads. Optimizing resources and combining files can reduce the number of requests.

- Image Optimization: Check image sizes and formats using tools like ImageOptim or online compression tools. Ensure images are appropriately sized and compressed.
- Code Minification: Use build tools like Webpack to minify CSS, JavaScript, and HTML files. Check the size of minified files to ensure efficient optimization.
- Tree Shaking: Use tools like Webpack to eliminate unused code from production builds. Analyze bundle sizes before and after tree shaking to gauge effectiveness.

- Responsive Design: Test the application on various devices and screen sizes to ensure responsiveness. Use browser developer tools or device simulators to simulate different environments.
- Efficient Navigation: Evaluate the number of clicks required to navigate through the application. User testing and feedback can help identify areas for improvement in navigation efficiency.

- Green Hosting: Research hosting providers that prioritize renewable energy or carbon offsetting. Check provider documentation or sustainability reports for information on energy practices.
- CDNs: Assess CDN performance and efficiency in delivering content. Look for CDNs with edge caching and efficient routing to reduce latency and energy consumption.

- CI/CD: Monitor build times and resource usage during CI/CD pipelines. Analyze build logs and performance metrics to identify bottlenecks and inefficiencies.
- Code Quality: Use code quality tools and linters to ensure clean and efficient code. Regular code reviews can help maintain code quality standards.

- Real-time Performance Monitoring: Set up monitoring tools to track performance metrics in real-time. Use alerts and notifications to identify performance issues promptly. - Carbon Emission Tracking: Estimate the carbon footprint of the application based on hosting provider energy usage and user traffic. Use carbon footprint calculators or sustainability metrics provided by hosting services.

- Efficient Analytics: Choose lightweight analytics solutions that prioritize data minimization and privacy. Analyze analytics data to identify opportunities for reducing data transfer and processing.
- Data Caching: Implement caching strategies to reduce redundant data fetching and improve load times. Monitor cache hit rates and effectiveness to optimize caching policies.
By systematically evaluating these aspects of your code and development processes, you can identify opportunities for improvement in energy efficiency and environmental sustainability.