Supported PHP Versions
Sympl uses the relevant version of PHP for your version of Debian, along with the typical PHP extensions, see Website Configuration Reference for details.
- PHP 7.3 for Debian Buster (Sympl 10.x)
- PHP 7.4 for Debian Bullseye (Sympl 11.x)
Since Debian and PHP each run different release schedules, Sympl often doesn't include the latest version of PHP. Debian handle providing backported security patches for their packaged versions of PHP [1] so using old versions of PHP isn't a cause for concern providing you use a supported version of Debian.
Using a different PHP version
Not currently supported, however it is on the roadmap[2] for some point in the future.
(If you really need a different version you could consider taking inspiration from "Multiple PHP versions" section in Enable HTTP2 Support in Apache at your own risk, however this is Community Documentation and not officially supported.)
Multiple PHP versions selected per-site
Not currently supported, however it is on the roadmap[3] for some point in the future.
(If you really need a different version you could consider taking inspiration from "Multiple PHP versions" section in Enable HTTP2 Support in Apache at your own risk, however this is Community Documentation and not officially supported.)