DAL (data access layer, I presume): PDO or any of the other competing access layers. Talking to a database is not an issue with PHP. You repurpose business log

DAL (data access layer, I presume): PDO or any of the other competing access layers. Talking to a database is not an issue with PHP. You repurpose business logic to different environments by maintaining good separation of concerns, which is definitely doable in PHP despite the prevalence of crappy PHP code out there. That's a community problem. Faulting PHP for not having "compile-time type checking" is like faulting a car for not flying. The solution for PHP performance is opcode caching. You certainly aren't going to write novel Monte Carlo simulation code in PHP, though - that's not what it was designed for. You have to evaluate a language/platform against its design goals, and failing to do that just broadcasts ignorance. Any other questions?