Migration of a Complex Application to Current PHP / Symfony Version
The customer's extensive, grown-over-the-years application was based on outdated versions of PHP and Symfony. The rather rigid update policy of PHP and also Symfony has led to a growing barrier to tackling migration.
Since the application was connected to a number of other systems, incoming connections were replaced by test data simulators and outgoing connections through stubs, putting the application in a sandbox. The developers were able to work under realistic conditions at any time.
Because the application is mission-critical, high test coverage was achieved through unit testing and end-to-end testing prior to migration. As a result, the quality of the application was monitored and ensured during the entire migration phase. An accumulation of problems, which only emerge in the final phase and lead to recurring delays, could thus be avoided. The schedule could be kept exactly.
Already without further measures for the performance optimization the application is twice as fast under the current PHP version. The number of application servers required could be reduced by half, resulting in significant cost savings.
As part of the migration, selected application modules have been refactored, making them easier and faster to extend and maintain. In addition to closing vulnerabilities of the outdated PHP version other security issues could be solved as well. Performance enhancements have been made to selected, critical modules, improving the user experience and further reducing resource requirements.
The customer now runs his application significantly more cost-effective. In addition, the application is now safer, more powerful and easier to maintain.