@xala3pa introduced in Greach the Grails Money Plugin. The idea is: instead of using a BigDecimal you use a class called Money which encapsulates the amount and currency. I've worked in the past with Grails web applications where I mapped money with a BigDecimal and I have been suffering the same problems as Alvaro explained through his talk (number format logic spread though the code base, rounding modes ...).
You can use the Money class in your domain classes. It will map into two columns in your database.
Although the github repository lacks more documentation, he showed through the talk rounding capabilities, currency exchange, a taglib and other features.
His slides are worth reading because he zooms out and talks about the designs motivations. (Cohesion, encapsulation, primitive obsession, feature envy ...). I fall a lot of times in the primitive obsession trap.
We are going to map in the short term In-App Purchases in some of our domain classes and I will look forward to have the Money Plugin as my ally.
@burtbeckwith introduced a library called GORM-Util during his Greach talk. The library tackles one of my biggest pain in Grails developing:
When you turn on logSql = true the queries displayed use question marks instead of the supplied values and a myriad of aliases. It makes extremely painful and difficult to understand if the generated query is what you are looking for. The library assists in getting rid of the aliases clutter and replaces the question mark with values.
The library also contains a Many to Many Trait which will definitely appear in the near future in the Spring Security Core Plugin implemented by the UserRole class.