PHP_VERSION_COMPATIBILITY.md

PHP version compatibility

Declared minimum

• composer.json: "php": ">=5.6"

Application code (excluding vendor)

Feature	Minimum PHP	Used in
Short array []	5.4	access.php, dal.php, register.php, requestuniqueidrange.php
__DIR__	5.3	register.php, requestuniqueidrange.php
session_set_cookie_params(lifetime, path, domain, secure, httponly)	5.2	access.php, dal.php
PDO	5.1	dal.php
array()	4	dal.php, utils.php, etc.

Current state

• Session code uses the 5-argument form of session_set_cookie_params() only (no array form, no samesite), compatible with PHP 5.2+.
• No null coalescing (??) – uses isset() ? : default for PHP 5.6.
• Conclusion: The application is compatible with PHP 5.6 through 8.x.

Note on SameSite

PHP 5.6 cannot set the SameSite cookie attribute. Browsers will use their default (often Lax). For stricter control, use PHP 7.3+ or set the cookie via a custom Set-Cookie header.