[antihero]

If you have lots of backend services, building a gateway API (aka BFF) using GraphQL is really nice. Your GQL handles composition of all the resources into exactly what the client needs for something, without having to define a REST endpoint for every single use case.

On the frontend you compose the various schemas that each component needs (fragments) and can in one request pull exactly the data needed with one request to the gateway which will use the minimum required calls to the upstream services, and execute them in the most efficient order.

[necovek]

> gateway API (aka BFF)

A gateway API is an API that gates other APIs. A BFF is a gateway API used for a particular purpose, clearly identified by the name ("backend for frontend").

Thus, they are not the same: one is a wider term, another is a focused implementation of that concept.

[patmorgan23]

And you can have multiple Backeds for Frontends different types of clients (i.e. browser, mobile)

[diurnalist]

This is very true! In practice I have seen that it is exceedingly difficult to write the GraphQL "sinks" (I don't recall the exact term) that can intelligently handle things like batching and understanding things like pre filtering, where one service in the composed call could and should be performed first to limit the result set. YMMV, in my experience it can be simpler to be more explicit about these things, especially when in "true" BFF the client team is also responsible for their immediate backend, which can give them that flexibility, at the cost, perhaps, of more boilerplate.