This is a very basic example of using Apollo Federation with local services. Normally Apollo Gateway works with remote services, but it still allows to use local schema if you know how the internal works.
Read more about this here: https://patrick.wtf/posts/apollo-federation-local-services
This example wraps https://countries.trevorblades.com/ under Apollo Federation, to demonstrate how to run Apollo Federation with local services (in this case, a schema that wraps a remote schema) and also how to add federation directives to pre-existing schemas using graphql-transform-federation.
To run make sure you have a recent version of node and run the following commands:
npm install
npm run start
Then should be able to access the Playground at http://localhost:4000/