Hello, Currently, I have a build chain, completly manage by automake, like: .vala > .c > .o > .exe I would like add a new step for preprocess a XML file .ui into a vala source: .ui > .vala > .c > .o > .exe I did this, in makefile.am gtkbuilder2vala_SOURCES = \ abstract-window.ui \ main.vala \ $(NULL) And: XSLTPROC = xsltproc .ui.vala: $(XSLTPROC) ... But make don't understand: make: *** No rule to make target `abstract-window.c', needed by `gtkbuilder2vala-abstract-window.o'. Stop. This seems to be a limitation of make: http://www.ensta.fr/~diam/dev/online/autoconf/autobook/autobook_180.html if the translation takes three steps--from .m' to.x', then from .x' to.c', and finally to `.o'---then Automake's simplistic approach will break. Have you another idea?