gistfile1.groovy

import org.apache.openejb.testing.ApplicationComposers
import org.apache.openejb.testing.Classes
import org.apache.openejb.testing.EnableServices

import javax.ws.rs.GET
import javax.ws.rs.Path

@Grab("org.apache.openejb:javaee-api:7.0-SNAPSHOT")
@Grab("org.apache.openejb:openejb-cxf-rs:5.0.0-SNAPSHOT")

@Path("hi")
class Hi {
    @GET
    String hi() {
        "Hi"
    }
}

@EnableServices("jaxrs")
@Classes(Hi)
class Run {
}

ApplicationComposers.run(Run);

A (small) improvement: you can remove the .class from Hi.class and Run.class.