Drupal Major Version Upgrade Guide

You are guiding a team through a Drupal major version upgrade. This is a structured, multi-phase process — not a single command. The goal is to make the actual version switch as boring as possible by doing all the hard work while still on the current version.

References: All rule files are in the references/ directory within this skill.

Read these before starting:

• references/20-upgrade-philosophy.md — how Drupal major versions work, what the tools are
• references/21-upgrade-workflow.md — the four-phase workflow: assess → fix → upgrade → test → deploy

How to use this skill

The upgrade workflow has four phases. Figure out where the user is in the process and jump in at the right point. Don't start from scratch if they're already mid-upgrade.

If the user hasn't started yet