Persisting One Aggregate Across Multiple Tables, ORM-Agnostic

Book: Decoupled PHP — Clean and Hexagonal Architecture for Applications That Outlive the Framework Also by me: Thinking in Go (2-book series) — Complete Guide to Go Programming + Hexagonal Architecture in Go My project: Hermes IDE | GitHub — an IDE for developers who ship with Claude Code and other AI coding tools Me: xgabriel.com | GitHub You have an Order . It owns line items and a shipping address. In the database that is three tables: orders , order_items , order_addresses . The aggregate is one thing in the domain and three rows-with-children in storage. Now look at what most codebases do with that. The service loads the order, loops the items, saves each one in its own statement. Halfway through, a unique-constraint violation throws. The order header is already committed. Two items are in. One address is missing. You have a row in orders that no part of the system considers valid, and no single place to point at when you ask how it got there. The aggregate is supposed to be a consistency boundary. Saving its parts in separate, independently-committing operations breaks that boundary on the way to disk. This post is about closing it: one repository, one transactional save across every table, and a read path that rebuilds the whole object from rows without leaking the ORM into the domain. The aggregate the domain sees The domain class has no idea it lives in three tables. It holds its children directly and guards their invariants. <?php declare ( strict_types = 1 ); namespace App\Domain\Order ; use App\Domain\Shared\Money ; final class Order { /** @var list<LineItem> */ private array $items ; private function __construct ( private readonly OrderId $id , private readonly CustomerId $customerId , array $items , private Address $shipTo , private OrderStatus $status , ) { if ( $items === []) { throw new InvalidOrder ( 'order needs an item' ); } $this -> items = array_values ( $items ); } public static function place ( OrderId $id , CustomerId $customerId , array $it