PHP 7.3 reached end of support in December 2021 and Adobe Commerce 2.3.x reaches end of support in September 2022. You may want to consider planning your upgrade now to Adobe Commerce 2.4.x and PHP 7.4.x to help maintain PCI compliance.

Coding Standards

Like many large projects, Magento has coding standards.

Use Magento’s coding standards when you contribute to Magento’s codebase or create extensions.