Upgrade Rails

When to use

Use this skill when upgrading Rails to a newer minor or patch version.

Background

Based on the Smooth Ruby and Rails Upgrades methodology. Key principles:

• Move by minor versions — upgrade incrementally through each minor version to the latest patch, never skip minors
• Separate Ruby and Rails upgrades — never combine them in one step
• Backport-first — preparatory commits (gem updates, deprecation fixes) land on main first, then the version bump is a small final step
• Small, reversible changes — each commit leaves tests green and is independently deployable

Upgrade strategy