PHP runs on server not client.
If you mean on client, then yes there are JavaScript Miners.
What do you even *mean* when you say server and client?
I'm a programmer who wants to know the technical aspects of writing a bitcoin miner in PHP.
I asked for a php miner and not a JavaScript miner.
I don't know what your trying to do but it fails on all levels. If you want to learn PHP don't pick a
crypto miner application, choose something more appropriate like a web client.
If you want to learn cryptography choose a language strong in computation like c++, PHP is not.
Also pick an algorithm where CPU mining is still viable, scrypt is not.
If you just want to mine scrypt coins forget about using a CPU or even a GPU, scrypt is dominated
by ASICS. Or choose another algorithm and use one of the many fine miners that already exist.