diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 4ecaac262..ff17b5617 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -43,7 +43,7 @@ jobs:
 
       - name: Install ikiwiki
         run: |
-          apt-get install \
+          apt-get install -y --no-install-recommends \
             ikiwiki \
             libtext-multimarkdown-perl \
             libimage-magick-perl \
@@ -58,17 +58,20 @@ jobs:
             texlive-latex-extra \
             texlive-latex-recommended \
             texlive-pictures \
-            graphviz
+            graphviz \
+
+          apt-get install -y --no-install-recommends \
+            dvipng # for teximg plugin
+
+          apt-get install -y --no-install-recommends \
+            mupdf-tools # for mutool
 
           # not latest version
           #apt-get install \
             #tj3
 
-          apt-get install \
-            dvipng # for teximg plugin
-
-          apt-get install \
-            mupdf-tools # for mutool
+          apt-get install -y --no-install-recommends \
+            ruby-rubygems # for taskjuggler
 
           cpanm --local-lib=~/perl5 local::lib && eval $(perl -I ~/perl5/lib/perl5/ -Mlocal::lib)
           cpanm -n YAML::Any YAML::XS Sort::Naturally LaTeXML