Lesson 3 — Upgrading Custom Code in TYPO3
Prerequisites and goals
Prerequisites
Theoretical prerequisites
This lesson assumes that you already know the following:
- Master TYPO3's version numbering system
- Understand LTS (Long Term Support) release policies
- Learn about security patches and maintenance releases
- Grasp upgrade path planning between versions
Practical prerequisites
Before you start this lesson, please have the following things ready:
- Create version upgrade roadmaps
- Identify critical path dependencies
- Plan maintenance windows for updates
- Evaluate version-specific features and changes
Goals
Theoretical goals
By the end of this lesson, you should know the following:
- Understand extension compatibility requirements
- Learn about API changes between versions
- Master code migration strategies
- Understand backward compatibility layers
Practical goals
By the end of this lesson, you should have completed the following:
- Update custom extensions for newer versions
- Implement code compatibility fixes
- Test extension functionality post-upgrade
- Document code migration changes