rails-upgrade-3-to-4

What problem does it solve?

Upgrading a legacy Rails 3.x application to Rails 4.x involves numerous breaking API changes, deprecated patterns, and compatibility pitfalls that can break existing functionality and waste significant development time if handled incorrectly.

Core Features & Use Cases

• Phased Upgrade Path: Provides the recommended 3.2 → 4.0 → 4.1 → 4.2 hop sequence to ensure no critical intermediate changes are skipped.
• Legacy Mass-Assignment Migration: Offers a safe transitional bridge from attr_accessible/attr_protected to strong parameters using the protected_attributes_continued gem, avoiding risky all-at-once rewrites.
• Compatibility Fixes: Covers Turbolinks integration, asset pipeline overhauls, Active Job migration for background workers, and gem compatibility audits for common Rails 3-era dependencies.
• Use Case: A team maintaining a 3-year-old Rails 3.2 internal tool can use this skill to upgrade to 4.2 without breaking existing user authentication flows or custom jQuery event handlers.

Quick Start

Use the rails-upgrade-3-to-4 skill to plan a safe, phased upgrade path for your Rails 3.2 application, including a transition plan for attr_accessible and Turbolinks compatibility.