Migration Checklist Per Version

A PHP runtime upgrade is an application change. Review every intervening migration guide, update dependencies, exercise representative traffic, and prepare rollback before changing production.

Use This Reference When

• Inventory runtime versions and extensions.
• Read new features, backward-incompatible changes, deprecations, and removals for each step.
• Run automated checks and staging smoke tests.
• Deploy observably with rollback prepared.

Upgrade Record

current runtime and extensions
target runtime and extensions
intervening migration guides reviewed
dependency compatibility checked
tests, static analysis, and smoke paths passed
staging metrics reviewed
production rollback documented

Upgrade in controlled increments when the application, dependency tree, or operational risk is substantial.