Don't quote me on this, but years and years ago, I almost seem to recall adding stuff to the built-in targets:

install::
        shell command \
        do things

dist::
        ....
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Update: In fact, something like this:

install:: cgi conf graphics docs libs templates retest
clean:: clean_sourcedirs clean_test

cgi:
    install -m 0500 -o www -g www src/cgi-bin/accounting.cgi ${CGIDIR}

clean_sourcedirs:
    rm -f doc/*.html
    rm -f doc/*.conf

clean_test:
    rm -f t/test.db
    rm -f t/test.conf-dist

... and other things called by the main directives, such as conf, grap
+hics for install...
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