Supporting opt-in nested mutations in GraphQL

Nested mutations in GraphQL offer a way to perform mutations on non-root types, potentially simplifying schemas by reducing redundancy and making them easier to comprehend. While the GraphQL specification does not support nested mutations due to the constraints of graphql-js, which relies on resolving fields in parallel, certain environments like PHP-based servers can implement them without these trade-offs. The feature could be made available as an opt-in option, allowing developers to benefit from enhanced schema simplicity while maintaining standard GraphQL behavior as the default. This flexibility allows nested mutations to coexist with traditional query and mutation roots, under a unified Root type, enhancing the ability to execute complex, nested operations akin to browsing data model relationships. Although not part of the official spec, offering nested mutations as an alternative can provide significant benefits without disrupting existing functionalities, allowing for more streamlined and efficient mutation processes.