Legacy PHP CRM Upgrade

I have a twenty-year-old, PHP-based CRM running in Docker on Google Cloud. The core interface works well for my team, so I want to preserve the current look and feel while modernising the stack from PHP 5.7 and MySQL 7.0 to supported versions. Your first task is to review the repository, plan the version jumps, handle any deprecated functions, and adjust the Docker images accordingly. Once the code compiles and runs, I will need thorough regression testing on three critical areas: • Customer records and search • Reports and data exports • User logins and permissions The system also sends and receives email and pushes data to our accounting and reporting tools, so those touchpoints must survive the upgrade unchanged. When everything passes, please deploy the refreshed containers back to our Google Cloud project and document the build, migration, and rollback steps. After go-live, I may retain you for ongoing updates and maintenance if the collaboration goes smoothly.