ADR-002: Manual service wiring without DI container (legacy)

Status

Accepted (migration planned)

Context

The application was bootstrapped as a slim PHP project where all services are instantiated manually inside src/routes.php. At the time, a DI container was considered unnecessary overhead for the initial scope.

As the project grew to 80+ services and 300+ routes, the manual wiring became a maintenance burden: every new dependency requires editing routes.php, services are eagerly instantiated on every request, and duplicate instantiations have appeared in 18+ locations.

Decision

The current approach is documented as legacy. New services must accept all dependencies through constructor injection so they are container-ready.

A migration to a lightweight PSR-11 container (PHP-DI or Slim's built-in container) is planned as Phase 3 of the architecture roadmap (see docs/architecture-tasks.md).

Consequences

• Adding a new service currently requires modifying routes.php.
• All services are created eagerly, even if the request only needs a subset.
• The transition to a DI container can happen incrementally: register one service at a time while the manual wiring continues for unregistered services.