Explain advanced GraphQL federation architecture and scaling strategies in PHP ecosystems.

GraphQL federation composes distributed schemas from multiple services into a unified API gateway while enabling independent service ownership.

As organizations scale, monolithic GraphQL schemas become difficult to manage.

Problems include:

GraphQL federation solves this by allowing independent services to contribute schema fragments.

Core concepts:

Independent service schemas.

Composes unified federated schema.

Cross-service object composition.

Gateway optimizes distributed execution.…