Ruby on Rails (RoR) has become a favorite among developers for various compelling reasons. First and foremost, it emphasizes convention over configuration, allowing developers to focus on building applications rather than configuring their environment. This simple yet powerful philosophy means that developers can quickly get started on a project without getting bogged down in repetitive setup tasks. Secondly, RoR boasts a robust ecosystem of libraries, known as gems, which enable the rapid implementation of complex features without reinventing the wheel. This means less coding time and more opportunity to refine user experience.

Another key factor is the active community supporting Ruby on Rails. With a wealth of knowledge available through forums, documentation, and tutorials, developers can easily find the help they need. Furthermore, RoR adheres to the DRY (Don't Repeat Yourself) principle, which helps to keep code clean and maintainable, enhancing overall productivity. Lastly, RoR is particularly well-suited for startups, as it enables rapid prototyping and iterative development, allowing teams to bring their ideas to market faster than ever. In summary, the combination of simplicity, a rich ecosystem, community support, and rapid development makes Ruby on Rails a developer's best friend.

Building a scalable application with Ruby on Rails involves several crucial steps that ensure your app can handle increased traffic and data load efficiently. First, start by establishing a solid architecture. This means structuring your application in a modular way, leveraging Rails' MVC (Model-View-Controller) design pattern to separate concerns. Additionally, consider implementing background job processing using libraries like Sidekiq or Resque, which allows heavy tasks to run in the background, improving response time for users. It's also essential to optimize your database access, leveraging techniques such as eager loading to minimize the number of queries made during a single request.

Next, focus on scaling your server infrastructure. Utilizing services like Amazon Web Services (AWS) or Heroku can help you manage resources effectively. As your user base grows, you might need to implement a load balancer to distribute traffic across multiple server instances. This ensures that no single server becomes a bottleneck. Furthermore, consider using caching strategies, such as fragment caching and Russian Doll caching, to improve load times by storing reusable data and content. By following these best practices, you can build a resilient, scalable application that leverages the full power of Ruby on Rails.

Developing applications with Ruby on Rails can present various challenges, particularly for newcomers. One common issue is the steep learning curve associated with the Rails framework. Developers often find it challenging to grasp the conventions and structures of Rails, especially if they come from a background in a different programming language. To overcome this, investing time in Rails tutorials and engaging with community resources, such as forums and documentation, can greatly enhance understanding and familiarity. Additionally, working on smaller projects can provide a practical approach to learning the intricacies of Rails.

Another significant challenge is handling performance and scalability, especially as applications grow. The Rails framework, while powerful, may lead to bottlenecks if not optimized properly. To tackle this issue, developers should employ techniques such as database optimization, caching strategies, and background job processing. By implementing tools like New Relic for monitoring and utilizing Redis for caching, developers can significantly improve their application's performance. Regularly reviewing performance metrics and being proactive about optimization can help maintain a responsive and scalable application.