php The key points of the text are that it is part 3 of a series about Test Driven Development with Symfony and Codeception. The series covers the red-green-refactor cycle, unit testing, mocking dependencies, and code coverage reporting. In this part, the final feature of the application's P2P payment system is implemented using TDD. The text also discusses how to refactor the TransferController to use a service layer for transfer functionality, secure the transaction history endpoint by adding authentication checks, and generate code coverage reports using PCOV. The series concludes with recommendations for further learning on Test-Driven Development and encouraging readers to review the final codebase on GitHub.