Nx comes with dedicated documentation for each framework:

React AngularNode

Angular Nx Tutorial - Step 6: Proxy

You passed --frontendProject=todos when creating the node application. What did that argument do?

It created a proxy configuration that allows the Angular application to talk to the API in development.

To see how it works, open angular.json and find the serve target of the todos app.

1{
2  "serve": {
3    "builder": "@angular-devkit/build-angular:dev-server",
4    "options": {
5      "browserTarget": "todos:build",
6      "proxyConfig": "apps/todos/proxy.conf.json"
7    },
8    "configurations": {
9      "production": {
10        "browserTarget": "todos:build:production"
11      }
12    }
13  }
14}

Note the proxyConfig property.

Now open proxy.conf.json:

1{
2  "/api": {
3    "target": "http://localhost:3333",
4    "secure": false
5  }
6}

This configuration tells nx serve to forward all requests starting with /api to the process listening on port 3333.

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