php-8.2

PHP 8.2 Conventions

The key project convention: always use readonly class instead of per-property readonly.

Readonly Classes

// AVOID: readonly on each property
final class OrderSummary
{
    public function __construct(
        private readonly string $orderUuid,
        private readonly string $buyerUuid,
    ) {}
}

// CORRECT: readonly on the class
final readonly class OrderSummary
{
    public function __construct(
        private string $orderUuid,
        private string $buyerUuid,
    ) {}
}

Use readonly class when all properties should be readonly (most DTOs, value objects, services). Keep per-property readonly only when some properties need to be mutable.