I remember when my app/views folder was a complete disaster. I had deeply nested partials, instance variables floating everywhere, and logic hidden inside HTML tags. If I wanted to change the color of a button, I had to search through 50 different files.
In 2026, we don’t build Rails apps like that anymore. We use Components.
Components allow you to treat your UI like Lego blocks. You build a “Button” once, and you reuse it everywhere. It makes your code cleaner, easier to test, and much faster to write.
Here are the best Rails component libraries you should be using today to keep your monolith organized.
1. ViewComponent (The Gold Standard)
Created by the team at GitHub, ViewComponent is the most popular choice. It turns your views into Ruby objects.
Why I like it:
Instead of a “dumb” partial, you get a Ruby class and an HTML file. You can pass data into the class, and Ruby will yell at you if you forget a required parameter. It makes your UI “Type Safe.”
# app/components/button_component.rb
class ButtonComponent < ViewComponent::Base
def initialize(title:, url:)
@title = title
@url = url
end
end
<%= link_to @title, @url, class: "bg-blue-500 text-white p-2 rounded" %>
The best part? You can Unit Test your UI. You don’t need a slow browser test just to see if a button has the right text. You can test it in milliseconds using standard Minitest.
2. Phlex (The Speed Demon)
If you hate context-switching between Ruby and ERB, you will love Phlex.
Phlex is a new challenger that is taking the Rails world by storm. It doesn’t use .html.erb files at all. You write your HTML in Pure Ruby.
# app/components/card.rb
class Card < Phlex::HTML
def template
div(class: "p-4 border rounded shadow") do
h1 { "Hello from Phlex" }
p { "This is 10x faster than ERB." }
end
end
end
Why I like it:
- Performance: It is significantly faster than rendering ERB templates.
- No context switching: You stay in Ruby land. You can use standard Ruby loops, conditions, and methods without the messy
<% %>tags. - High ROI: For a solo developer, Phlex makes building complex UI kits feel like writing a normal script.
3. Lookbook (The Designer’s Secret)
If you are using ViewComponent or Phlex, Lookbook is a mandatory tool.
Think of it as a “Storybook” but for Rails. It creates a private dashboard in your development environment where you can see every component you’ve built.
How to use it:
- Install the gem.
- Mount the engine in your
routes.rb. - Visit
/lookbook.
You can now click through your buttons, modals, and navigation bars to see how they look with different data. It is the best way to maintain a consistent design system without getting lost in your own code.
4. Tailwind-Stimulus-Components
Components aren’t just about HTML; they are also about Behavior.
If you use Tailwind CSS (which you should), you don’t want to write custom JavaScript for every single dropdown or modal. This library gives you pre-written Stimulus controllers that handle the “boring” stuff.
Instead of writing a “modal-open” script, you just add a data attribute:
data-controller="modal">
data-action="click->modal#open">Open
data-modal-target="container" class="hidden">
