.PHONY: all clean
OUTPUT += tech-spec.pdf
all: $(OUTPUT)
%.pdf: %.tex
latexmk -pdf -xelatex -cd -latexoption="--shell-escape" -jobname="$*" $<
clean:
for f in $(basename $(OUTPUT)); do \
latexmk -CA -xelatex -cd -jobname=$$f; \
done