Typo3 extension upgrade

Skill netresearch/typo3-extension-upgrade-skill/skills/typo3-extension-upgrade

Agent Skill for systematically upgrading TYPO3 extensions to newer LTS versions | Claude Code compatible

Install

npx -y skills add netresearch/typo3-extension-upgrade-skill --skill typo3-extension-upgrade

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Use when upgrading TYPO3 extensions to newer LTS versions (v11->v12, v12->v13, v13->v14 - v14.3 LTS is the current target), running Extension Scanner, Rector, Fractor, PHPStan, fixing deprecated APIs, or resolving compatibility issues. Also triggers on: migration, version upgrade, deprecated API, dual-version compatibility, Fluid 5 strict VHs, HashService removal, ext_tables.php split.

SKILL.md

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TYPO3 Extension Upgrade Skill

Framework for upgrading TYPO3 extensions to newer LTS versions. Extension code only, not 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`

Core Workflow

Complete planning phase (consult references/pre-upgrade.md)
Create feature branch (verify git is clean)
Update composer.json constraints for target version
Audit third-party dependencies for major version changes (consult references/third-party-dependency-upgrades.md)
Run rector process --dry-run then review and apply
Run fractor process --dry-run then review and apply
Run php-cs-fixer fix
Run phpstan analyse against each supported dependency version and fix errors
Run phpunit and fix tests
Test in target TYPO3 version(s)
Verify success criteria (consult references/verification.md)

When NOT to Apply Automatically

Do NOT blindly apply Rector/Fractor when dual-version compatibility, missing tests, unclear changes, or complex APIs (DBAL, Extbase) are involved. Instead apply rules manually, testing between changes.

Third-Party Dependency Upgrades

When composer.json widens a dependency to a new major version: enumerate API usages, cross-reference the new API, verify mocks, use adapter pattern for signature differences, run PHPStan per major version. See references/third-party-dependency-upgrades.md.

Quick Commands

rector process --dry-run && rector process        # PHP migrations
fractor process --dry-run && fractor process       # Non-PHP migrations
php-cs-fixer fix && phpstan analyse && phpunit     # Quality checks

Asset Templates

Config templates in assets/: rector.php, fractor.php, phpstan.neon, phpunit.xml, .php-cs-fixer.php

References

Reference	Use when...
`references/pre-upgrade.md`	Planning checklist, version audit, risk assessment
`references/api-changes.md`	Checking deprecated/removed APIs by TYPO3 version
`references/api-traps.md`	Cross-version footguns: TCA restrictions, boot order, DI bypass
`references/upgrade-v11-to-v12.md`	Upgrading from TYPO3 v11 to v12
`references/upgrade-v12-to-v13.md`	Upgrading from TYPO3 v12 to v13
`references/upgrade-v13-to-v14.md`	Upgrading from TYPO3 v13 to v14
`references/dual-compatibility.md`	Dual compatibility (v12 + v13)
`references/real-world-patterns.md`	Real-world migration examples
`references/toolchain-output.md`	Rector/Fractor dry-run output
`references/troubleshooting.md`	Rector broke code, PHPStan errors, test failures
`references/third-party-dependency-upgrades.md`	Non-TYPO3 dependencies (major version bumps, adapter patterns)
`references/verification.md`	Success criteria and real-world testing
`references/multi-version-worktrees.md`	Per-LTS worktree layout, backport workflow, cross-version CI matrix
`references/audit-mode.md`	Assessing/estimating: ticket only non-automatable findings
`scripts/scan-deprecations.sh <path>`	Deterministic grep scan for deprecated/removed APIs and traps

External Resources

What ships with it: 21 files

148.6 KB alongside SKILL.md, 4 of them executable