This buildfile is part of projectlombok.org. It builds the mapstruct-lombok binding; we think the version on mavencentral is the last version that is ever needed; the code itself is trivial and exists as a separate dependency solely because it is itself dependent on both lombok and mapstruct. lombok.mapstruct.NotifierHider$AstModificationNotifier mvn is not on your path and/or MAVEN_HOME is not set. Add mvn to your path or set MAVEN_HOME to continue.