Working on a legacy Rails codebase can be challenging. But you can start navigating and working on it effectively with a good strategy. This blog post discusses common steps when working in a legacy codebase. This article does not talk about optimizing the codebase; it is only about understanding and navigating it. Because it does not make any assumptions.

Before Rails 8 we always used something like the devise gem for authentication. Even though Rails has all the features to build authentication, It was difficult to implement compared to devise gem. Rails 8 addresses this problem with an authentication generator. One good thing about this is that it is completely optional as a generator. You can still go with other authentication providers or build it yourself. The Rails 8 authentication generator includes login, logout, and password reset features. But interestingly it does not include a user registration feature. As per DHH, it is because “those are usually bespoke to each application”. But it is easy to implement. I have created a Rails app template for basic user registration generation. You can easily generate user registration using that.

As Rails developers, we often focus on writing clean, efficient Ruby code. However, as the application grows optimizing database performance is equally crucial for creating responsive applications. One of the most powerful tools in our arsenal for database optimization is indexing. Here I will talk about PostgreSQL indexing from a Rails developer’s perspective. The query plan generated by EXPLAIN will help us to make informed decisions about index creation, ensuring our database queries run as efficiently as possible.

Rails Active Record is a powerful ORM that simplifies database operations, but complex queries can sometimes lead to performance issues. We can use EXPLAIN to find out details about why a query is not performing well. In this post, we’ll explore the Active Record Explain feature and how to understand it’s output. We’ll cover the basics of using Explain, interpreting its output, and give you some hints on applying that knowledge to optimize your database queries. EXPLAIN is a database-level feature. We will be using PostgreSQL for this post. EXPLAIN provides insights into how the database executes your queries, helping you identify and resolve performance issues.

The convenience and power of Active Record allows you to interact with your database in a more Ruby-like way, making it easier to write efficient and readable code. However, as with any complex system, performance can sometimes take a hit when using Active Record. One common scenario where performance may suffer is when counting records in your database. In any Rails app, A simple count method call can quickly become a bottleneck, especially for larger datasets. In this post, we’ll dive into some optimization techniques for using Active Record’s count method in your Rails app.

In Ruby on Rails, A generator is a tool that helps create scaffolding (basic code structure). By default, Rails provides several built-in generators like rails generate scaffold, rails generate controller, etc. Many of the gems come with their own Rails generators too.

A custom generator is used to create a customized scaffolding for your application. Custom generators in Rails allow developers to create their code generators to streamline repetitive tasks and enforce consistency across the codebase.

When building applications in Ruby on Rails, We store data in Plain Old Ruby Object (called PORO) value objects. This is a common pattern, We store data directly in service objects using attr_accessor. But in some cases we might have to cast data from string. For this, we do have to cast those attributes.

Active Record strict loading is an awesome feature in Rails that can significantly improve your application’s performance by preventing N+1 queries. In the past days before Rails 6.1, We mainly used bullet gem to statically scan this. But now, It can be explicit in the code using strict_loading. Let’s see what strict loading is, how to use it, and see some examples.