How to setup a custom PHP package?

[Sergei G]

Hi,

I have discovered that one PHP app I am running in a jail needs PHP 
built with --enable-mbstring option.  It appears that 10.2 is not 
compiled with that option.

So, I need to build a custom PHP package and load it into a jail. How do 
I do that?  I have never setup a custom package repository.

I hope I can build just the PHP and may be PHP-FPM and nothing else in 
my custom repo.  I'd like the rest of the packages to be loaded from 
standard repositories as usual.


Thank you