value-objects-and-dtos_skill

Overview

This skill applies production-grade Symfony architecture and execution workflows focused on value objects and DTOs. It provides a controlled, incremental approach with clear checkpoints, validation, and an auditable decision log. Use it to reduce coupling, improve data integrity, and manage medium-to-complex changes safely.

How this skill works

I start by mapping current boundaries, constraints, and coupling points that affect value objects and DTOs. I propose the smallest coherent architectural adjustment needed, then execute changes in iterative checkpoints with validation at each stage. At the end I summarize tradeoffs, residual risks, and a prioritized follow-up backlog.

When to use it

• When refining data modeling and immutability rules for domain value objects.
• When introducing or standardizing DTOs for API input/output and service boundaries.
• When planning medium or complex changes that risk cross-cutting coupling.
• When you need auditable checkpoints and rollback-safe execution.
• When the project lacks consistent patterns for mapping, validation, or lifecycle of DTOs/value objects.

Best practices

• Prefer existing project patterns and extend them minimally rather than broad rewrites.
• Isolate changes behind clear interfaces and mapping layers to limit blast radius.
• Execute in small checkpoints and validate with unit and integration tests at each step.
• Keep a concise decision log recording rationale, alternatives, and tradeoffs.
• Document residual risks and convert them into a prioritized follow-up backlog.

Example use cases

• Introduce immutable value objects for monetary amounts and replace ad-hoc arrays across services.
• Create a standardized DTO layer for a public API release, including versioned mappers and validators.
• Refactor a service boundary to accept DTOs instead of domain entities to reduce coupling.
• Add incremental validation and mapping tests while keeping production behavior unchanged until final cutover.