1999-present Lecturer of Computer Science, University of St Andrews. 1997-1999 Lecturer of Computer Science, University of Edinburgh. 1996-1997 Research Associate, Imperial College of the University of London. 1990-1991 Software Engineer, Nutec Informatica, Brazil. 1986-1990 System designer, Altus Sistemas de Informatica, Brazil. 1984-1986 Computer programmer, UFRGS, Brazil.