diff --git a/Dockerfile b/Dockerfile
index 24dbc64..91d8a3c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -6,3 +6,4 @@ RUN sed -i 's/65534/1000/' /etc/passwd
 # install additional requirements
 RUN apt-get -qy update
 RUN apt-get -qy install ca-certificates curl make git inkscape texlive-full xz-utils biber texlive-bibtex-extra latexmk
+RUN apt-get -qy install pdftk 
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