My frontend is `localhost:3000`, and my GraphQL server is `localhost:3333`.

I've used react-apollo to query/mutate in JSX land, but haven't made a query/mutation from Express yet.

I'd like to make the query/mutation here in my `server.js`.

```
server.get('/auth/github/callback', (req, res) => {
  // send GraphQL mutation to add new user
});

```

Below seems like the right direction, but I'm getting `TypeError: ApolloClient is not a constructor`:

```
const express = require('express');
const next = require('next');
const ApolloClient = require('apollo-boost');
const gql = require('graphql-tag');

// setup
const client = new ApolloClient({
  uri: 'http://localhost:3333/graphql'
});
const app = next({dev});
const handle = app.getRequestHandler();

app
  .prepare()
  .then(() => {
    const server = express();

    server.get('/auth/github/callback', (req, res) => {
      // GraphQL mutation
      client.query({
        query: gql`
          mutation ADD_GITHUB_USER {
            signInUpGithub(
              email: "email@address.com"
              githubAccount: "githubusername"
              githubToken: "89qwrui234nf0"
            ) {
              id
              email
              githubToken
              githubAccount
            }
          }
        `,
      })
        .then(data => console.log(data))
        .catch(error => console.error(error));
    });

    server.listen(3333, err => {
      if (err) throw err;
      console.log(`Ready on http://localhost:3333`);
    });
  })
  .catch(ex => {
    console.error(ex.stack);
    process.exit(1);
  });

```

[This post mentions Apollo as the solution](https://stackoverflow.com/questions/52832210/how-to-call-graphql-api-from-node-js-express-server), but doesn't give an example.

How do I call a GraphQL mutation from Express server `:3000` to GraphQL `:3333`?