Pratical Grails 3 Book Cover

Grails 3: A Practical Guide to Application Development

The first book dedicated to Grails 3. You will learn the concepts behind building Grails applications. Real, up-to-date code examples are provided so you can easily follow along.

eBook Edition
based on Grails 3.3.8

This book layed out into 6 sections with multiple chapters

Introduction to Grails

In this section you are introduced to the basic concepts behind a Grails application. As we progress we will show you how to test what we are building.

  • Community
  • Getting Setup
  • Domain Model & GORM
  • Controllers
  • Views (GSP & JSON)
  • Services


Plugins are a huge part of the success of Grails. They provide a lot of functionality out of the box to get you going quickly.

  • Introduction to Plugins
  • Using common community plugins
  • Taking advantage of Spring Boot Starters
  • Creating your own plugins


The web is powered by rest APIs and Grails 3 provides you quick and easy ways to build performant APIs to power your mobile apps or websites.

  • Building APIs in Grails
  • @Resource
  • The RestfulController
  • Customize API behavior
  • Custom routing

Reactive Grails

Reactive is all the hotness right now. We'll go over what a reactive application is and how Grails makes it easy to use this pattern in your applications.

  • Reactive Concepts
  • Events in Grails
  • Events by Example
  • RxGORM

Building & Deploying

How you deploy, and mantain your Grails applications is just as import as how you build it. We will go over battle proven deployment and operation scenarios.

  • Continous Integration
  • Continous Deployment
  • Configuration
  • Operations & Monitoring

Grails By Example

Here is where we will use everything we've learned in previous sections to build out a more complex web application.

  • Build a fully featured website.
  • Full JSON API
  • Multi Tenant aware (Grails 3.2)
  • Common plugin usage
  • Delivery Pipeline

About the Author

Author Eric Helgeson

Eric Helgeson

Eric is a developer who has been working with Grails from 1.x to the latest 3.x line. He has spoken at GR8Conf US on Grails and is an active member in the Grails community.

His experiences include building, maintaining, and operating massive web API system built around Grails as well prototyping sites. He is currently consulting on Grails 2 and 3 applications as well as running his own startup - which of course is built on Grails 3.