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Best practices and rules of thumb when developing for TYPO3.
This chapter aims to give developers some ideas and practices at hand when PHP architectural decisions have to be taken. Result should be a understanding of some thoughts behind and a harmonization of solutions found in the TYPO3 CMS core and maybe in third party extensions. It should help reviewers to evaluate solutions and how they stick to the main code separation principles the core tries to follow. The document should help developers to train their architectural skills and to rate easier which pattern matches a given problem to improve code quality and exchangeability.