Also pdfrw (https://github.com/pmaupin/pdfrw) is a pure-python implementation but I have never used it

I like the idea. 👍

Yes! That's better~

I suspect you have all moved on, as this project hasn't been touched in a year, but pdftk has been removed from deb & ubuntu due to upstream dependencies (see https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=892539)

so changing this dependency would be awesome :-)

Another option is use latex with the pdfpages package. I use the following script, which I call as

pdfstack "${tmpfolder}"/background.pdf "${tmpfolder}"/foreground.pdf "${filename}.pdf"

in place of

(NOT tested much)

#!/bin/zsh

latex='xelatex'

bgf=$1
fgf=$2
out=$3
base=${out:r}

tmpdir=`mktemp -d`
fbase="${tmpdir}/${base}"
fbdir=${fbase:h}

/bin/mkdir -pv $fbdir
/bin/cp $bgf $fgf $fbdir
cat <<EOF > "${fbase}.tex"
\\documentclass{article}
\\usepackage{graphicx}
\\usepackage{pdfpages}

\\begin{document}
\\makeatletter
\\includepdf[pages=-,picturecommand={
  \\includegraphics[page=\\AM@page]{${bgf:t}}
}]{${fgf:t}}
\\makeatother
\end{document}
EOF

cd $fbdir
${latex} $fbase
cd -
cp "${fbase}.pdf" "${base}.pdf"

My suggestion here was to reduce the need for external dependencies, but your script is quite neat and also more portable than the original

We should probably collect all these solutions somewhere since in this repo looks like there is not much of a chance to make changes

My suggestion here was to reduce the need for external dependencies, but your script is quite neat and also more portable than the original

Sure. For me latex and pdfpages are basic tools, so this indeed saved me a lot of dependencies (all the java stuff around pdftk), but of course it depends on the setup

My suggestion here was to reduce the need for external dependencies, but your script is quite neat and also more portable than the original

By the way, it seems that the list of dependencies in the README is completely off...