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name: typo3-extension-upgrade description: "Agent Skill: Systematic TYPO3 extension upgrades to newer LTS versions. Covers Extension Scanner, Rector, Fractor, PHPStan, and testing. Use when upgrading extensions to newer TYPO3 versions or fixing compatibility issues. By Netresearch."

TYPO3 Extension Upgrade

Systematic framework for upgrading TYPO3 extensions to newer LTS versions.

Scope: Extension code upgrades only. NOT for TYPO3 project/core upgrades.

Upgrade Toolkit

Tool	Purpose	Files
Extension Scanner	Diagnose deprecated APIs	TYPO3 Backend
Rector	Automated PHP migrations	.php
Fractor	Non-PHP migrations	FlexForms, TypoScript, YAML, Fluid
PHPStan	Static analysis	.php

Planning Phase (Required)

Before ANY code changes for major upgrades (PHP version drops, TYPO3 major versions):

1. List all files with hardcoded versions (composer.json, CI, Docker, Rector)
2. Document scope - how many places need changes?
3. Present plan to user for approval
4. Track progress with todo list

See references/pre-upgrade.md for detailed planning checklist.

Generic Upgrade Workflow

1. Complete planning phase (above)
2. Create feature branch (verify git clean)
3. Update composer.json constraints for target version
4. Run rector process --dry-run → review → apply
5. Run fractor process --dry-run → review → apply
6. Run php-cs-fixer fix
7. Run phpstan analyse → fix errors
8. Run phpunit → fix tests
9. Test in target TYPO3 version(s)

Quick Commands

./vendor/bin/rector process --dry-run && ./vendor/bin/rector process
./vendor/bin/fractor process --dry-run && ./vendor/bin/fractor process
./vendor/bin/php-cs-fixer fix && ./vendor/bin/phpstan analyse && ./vendor/bin/phpunit

Configuration Templates

Copy from assets/ and adjust for target version:

• rector.php, fractor.php, phpstan.neon, phpunit.xml, .php-cs-fixer.php

References

Topic	File
Pre-upgrade checklist	references/pre-upgrade.md
API changes by version	references/api-changes.md
Real-world patterns	references/real-world-patterns.md

TYPO3 Changelogs

Version	Changelog
v14	Changelog-14
v13	Changelog-13
v12	Changelog-12

Success Criteria

• rector/fractor --dry-run show no changes
• phpstan analyse passes
• All tests pass
• Extension works in target TYPO3 version

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Contributing: https://github.com/netresearch/typo3-extension-upgrade-skill