1 Introduction

Dynamic frameworks like Rails and Django helped pave the way to a more modern way of thinking about web applications. Grails builds on these concepts and dramatically reduces the complexity of building web applications on the Java platform. What makes it different, however, is that it does so by building on already established Java technologies like Spring and Hibernate.

Grails is a full stack framework and attempts to solve as many pieces of the web development puzzle through the core technology and its associated plugins. Included out the box are things like:

• GORM - An easy to use Object Mapping library with support for , MongoDB, and more.

• A controller layer built on

• A plugin system featuring hundreds of plugins.

• Flexible profiles to .

All of these are made easy to use through the power of the Groovy language and the extensive use of Domain Specific Languages (DSLs)

This documentation will take you through getting started with Grails and building web applications with the Grails framework.

In addition to this documentation there are that walk you through various aspects of the technology.

Finally, Grails is far more than just a web framework and is made up of various sub-projects. The following table summarizes some other key projects in the eco-system with links to documentation.

Grails 4 ships with the following dependency upgrades:

• Groovy 2.5.6

• GORM 7 and Hibernate 5.4 (now the default version of Hibernate for new applications)

• Spring Framework 5.1.5

• Spring Boot 2.1.3

• Spock 1.2

Micronaut has also been used to improve startup and reduce overall memory consumption of Grails applications (along with associated improvements in Spring Boot 2.1).