Ruby on Rails

Ruby on Rails

Rails is a web application framework that includes everything needed to create web applications. Rails 8 (2025) simplifies deployment (Kamal) and reduces dependencies (Solid Cache/​Queue).

When to Use

• Startups: The "One Person Framework". Build a full SaaS alone.
• Rapid Development: Convention over Configuration makes you move fast.
• No-Build: Rails 8 pushes hard for "no-build" setups with Propshaft and import maps.

Quick Start

# app/​controllers/​posts_controller.rb
class PostsController < ApplicationController
  def index
    @posts = Post.all
  end
end

Core Concepts

The "Solid" Stack (Rails 8)

• Solid Cache: DB-backed caching (replacing Redis for simple cases).
• Solid Queue: DB-backed background jobs.
• Solid Cable: DB-backed WebSocket handling. Rails 8 aims to let you deploy with just a SQLite/​Postgres DB, no Redis required.

Hotwire

Build SAP-like responsiveness with HTML over the wire.

• Turbo: Fast navigation and partial page updates.
• Stimulus: Modest JavaScript frameworks for the remaining 10% of interactivity.

Kamal

The new default deploy tool. kamal deploy puts your app on any server using Docker.

Best Practices (2025)

Do:

• Use Solid libraries: Start with the default DB-backed queue/​cache. Scale to Redis only if needed.
• Use Hotwire: Avoid React/​Vue complexity unless the UI is extremely interactive.
• Use SQLite in Production: For small to medium apps, Rails 8 + optimized SQLite is a valid production stack.

Don't:

• Don't bloat models: Use Concerns or Service Objects (app/​services) for heavy business logic.

References

• Ruby on Rails Guides