Why do individuals and companies still say things like “We can't use Grails because we are a Java shop”? Do “Java shops” use Spring? Spring beans can be written in Groovy. Do “Java shops” use JSF? JSF backing beans can be written in Groovy. Contrariwise, most Grails artifacts can be written in Java. Grails is a Java framework, just like Spring, JSF, etc. It just happens to be the first one out with Groovy support.