diff --git a/buildserver/cookbooks/android-ndk/recipes/default.rb b/buildserver/cookbooks/android-ndk/recipes/default.rb
index bc704479..506443cb 100644
--- a/buildserver/cookbooks/android-ndk/recipes/default.rb
+++ b/buildserver/cookbooks/android-ndk/recipes/default.rb
@@ -41,9 +41,9 @@ script "setup-android-ndk-r10e" do
     else
        SUFFIX=''
     fi
-    chmod u+x /vagrant/cache/android-ndk-r10e-linux-x86$SUFFIX.bin
-    /vagrant/cache/android-ndk-r10e-linux-x86$SUFFIX.bin x
-    mv android-ndk-r10e #{ndk_loc}/r10e
+    cd #{ndk_loc}
+    7zr x /vagrant/cache/android-ndk-r10e-linux-x86$SUFFIX.bin
+    mv android-ndk-r10e r10e
   "
   not_if "test -d #{ndk_loc}/r10e"
 end
diff --git a/buildserver/cookbooks/fdroidbuild-general/recipes/default.rb b/buildserver/cookbooks/fdroidbuild-general/recipes/default.rb
index 3d7ca78d..6cde2f92 100644
--- a/buildserver/cookbooks/fdroidbuild-general/recipes/default.rb
+++ b/buildserver/cookbooks/fdroidbuild-general/recipes/default.rb
@@ -54,6 +54,7 @@ end
     openjdk-7-jdk
     openjdk-8-jdk
     optipng
+    p7zip
     pandoc
     perlmagick
     pkg-config