PHP upgrade
Security support for PHP 8.2 ends on 31 December 2026, and older versions are already unsupported. I review your code, adapt it to a current PHP version and fix the errors that appear after a switch.
Discuss a PHP upgradeStefan Pilz · over 15 years of PHP development · 100% remote
SERVICE OVERVIEW
A PHP upgrade means adapting your website or application so that it runs without errors on a current PHP version. I review the existing code and libraries, fix incompatibilities and test the key workflows before the new version goes live.
Once a PHP version no longer receives security updates, newly discovered vulnerabilities stay open. Sooner or later, hosting providers switch such versions or only offer continued operation for an extra fee. If the code does not run on the new version, the website shows error messages or simply goes blank.
It is better to plan the upgrade yourself: in a staging environment, with time to track down errors and without the pressure of a fixed switch-over date.
SERVICE SCOPE
Static analysis shows me the places in the code that no longer work with the target version or are marked as deprecated. The dependencies come next: Composer packages, frameworks, CMS extensions and PHP extensions on the server. You receive a list of all affected places and an estimate of the effort.
The older the starting version, the more there is to do. The old MySQL extension has been gone since PHP 7, and each() and create_function() were removed in PHP 8. Since PHP 8.1 and 8.2, passing null where a string is expected and creating dynamic properties, among other things, trigger warnings that will become errors in future versions. I fix these places properly instead of just hiding the messages.
Libraries are updated to versions that support the target PHP version. I replace unmaintained packages with alternatives. On the server I check extensions and settings so that nothing is missing after the switch, for example for sending email, image processing or encryption.
TYPICAL ERROR MESSAGES
I see these messages frequently in outdated code. If one of them appears on your site, the code is not compatible with the new PHP version.
Call to undefined function mysql_connect()The old MySQL extension has not existed since PHP 7. Database access has to be moved to mysqli or PDO, ideally with prepared statements, which also protect against SQL injection.
Call to undefined function each()each() and create_function() were removed in PHP 8. Older libraries, templates and CMS extensions are often affected. These places can usually be replaced with foreach and anonymous functions.
count(): Argument #1 ($value) must be of type Countable|arraySince PHP 8, calling count() on null or a scalar value causes an error instead of a warning. The code relied on behaviour that PHP no longer tolerates.
Creation of dynamic property … is deprecatedSince PHP 8.2, assigning a property that is not declared in the class triggers a warning. It still works but will become an error in a future version.
Passing null to parameter #1 … of type string is deprecatedSince PHP 8.1, PHP warns when built-in functions such as strlen() or trim() receive null. These messages often flood the log files.
500 Internal Server ErrorThe page shows nothing or only a generic error page because error messages are hidden on the live system. The actual cause is in the server's error log, and that is where I start.
RELEVANT EXPERIENCE
For a custom-built website, I adapted the existing PHP code to a new runtime. The anonymised project shows that an in-place upgrade can be possible; we assess the effort for your application separately.
Anonymised client project · Starting point
A website that had grown over time, with many individual PHP files, needed to stay in operation. The existing functionality and code were the starting point.
Same project · Result
The code was adapted and preserved. No complete rewrite was required for this project. Whether this approach suits your application is something we clarify in a review.
DELIVERABLES & SCOPE
We agree the deliverables before starting. Depending on the scope, these may include:
If parts of the application come from third parties and no compatible version exists, they have to be replaced or adapted. That can increase the effort. Without access to the source code, for example with encrypted extensions, adaptation is not possible.
For an initial assessment, details of the current PHP version, the system in use and any deadline from your hosting provider help. We agree the scope of the review and the implementation beforehand.
WORKING TOGETHER
I get access to the code and record the PHP version, dependencies and the key workflows of your website.
A copy of the website runs on the new PHP version, separate from live operation. Errors show up there without visitors noticing.
I fix the places found and test forms, login, orders and other important functions.
We switch the live website at an agreed time. A backup and the way back to the old version are prepared.
RELATED SERVICES
Move from older releases via the LTS versions to Symfony 7.4 or 8.
Find out which code is still needed and remove the rest safely.
Assess an established PHP application as a whole and develop it step by step.
QUESTIONS & ANSWERS
With many hosts that takes one click, and sometimes everything works afterwards. But you only find out whether your code is compatible after switching. It is safer to test the new version in a staging environment first. If you have already switched and errors appear, the version can usually be reverted temporarily.
PHP 8.5 receives security updates for longer, until the end of 2029. PHP 8.4 is currently supported by more libraries and extensions. The right choice depends on what your dependencies support. We clarify that in the review.
Maintained extensions usually have compatible versions. Extensions that are no longer developed are the critical ones. They can be adapted, replaced with an alternative or removed if they are no longer needed.
Yes. The adaptation happens in a staging environment. Only the actual switch affects the live website, and it is usually brief.
In many cases an upgrade costs less than a rebuild, even with very old code, as the project from PHP 5.6 to 8.4 shows. If the code is so tangled that every change creates new problems, I will tell you openly and we compare both options.
NEXT STEP
Tell me the current PHP version, the system in use and, if applicable, the deadline set by your hosting provider. I will get back to you with an initial assessment.
Your enquiry goes directly to me, Stefan Pilz. We agree the scope and costs before you commission any work.
I read your enquiry and get back to you. Together, we clarify your goals, constraints and open questions.
Depending on the project, we start with a specific implementation or an analysis agreed in advance.
You know which services and deliverables are included. We agree on scope, effort and costs before you commission the work.