Preparing an application for PHP 7.4

PHP 7.4 introduces useful language features and a new set of deprecations. The safest migration treats runtime, extensions and background processes as one release unit.

Run with complete error reporting

Collect deprecations for web requests, command-line jobs and queue workers. Review array access, nested ternaries, real-type handling and library compatibility before production logs are required to identify the remaining paths.

Compare extensions and settings

Build an explicit manifest of extensions, INI values, locale, timezone and process-manager behaviour. Confirm database, cache, image and internationalisation modules against production-shaped data.

Canary the runtime

Place a small worker pool on PHP 7.4, route controlled traffic to it and compare errors, latency and memory. Ensure sessions and cached serialised values remain compatible before expanding or rolling back.