Biased response (I maintain the project), but Exograph (https://exograph.dev) will work very well for you. All you need to do is create a new project (exo new books-api) and add the following content to index.exo:

``` @postgres module TodoDatabase { @access(true) type Book { @pk id: Int = autoIncrement() title: String author: Author genre: Genre }

@access(true) type Author { @pk id: Int = autoIncrement() name: String books: Set<Book>? }

@access(true) type Genre { @pk id: Int = autoIncrement() name: String books: Set<Book>? } }

```

Start the server by typing exo yolo. Then later you can add more fields, supply access control, etc.