I had a lot of hurdles to make Hibernate ORM run and build on Mac OS X and IntelliJ IDEA so here are a few tidbits: I give Gradle 1GB export GRADLE_OPTS="-Xmx1024M" Gradle hangs on me after ~ 2300 to 2400 tests for hibernate-core subsystem. Basically at least one of the worker hangs for ever. To work around that I forced Gradle to use one thread ./gradlew -no-daemon --parallel-threads 1 clean test IntelliJ IDEA does not import ORM properly on Mac OS X. I tried both to run IDEA with Java 6 (default) and Java 7 (hacked). The way around that is to use `./gradlew idea` and open the project in the IDE. You then have to manually add the generated source directory in a few modules. Things are explained here: https://community.jboss.org/wiki/ContributingToHibernateUsingIntelliJ Emmanuel