You should be ok as long as you don't distribute the software.
The only real purpose of the gpl is if you distribute the program, you must make source code available. You can't take the php framework you want to use, add your code, then sell it encoded with zend encoder for example. You must provide the source. If the framework was LGPL, you could 'plug' your code in, and encrypt/encode that, and you'd be fine, as long as the source or any modifications to the LGPL part were made public. That is how GTK+ works.
So, as long as you don't distribute your code, you're fine.