This is one recent feature that perhaps deserves some more popularization - jetbrains.mps.baselanguage.logging has been enhanced with two logging statements, which replace the now deprecated logging statements like error, warn, info and others: message outputs a logging message into the MPS Messages view and so provides a very convenient instant way to trace your code. If multiple projects are open in MPS, an optional project parameter can be used to target the Messages view of a particular project. log forwards a logging messages to the log4j library using the configuration in $MPS_HOME