Copier allows you to run post render tasks, just like cookiecutter. These are defined as a list of tasks in your copier.yml. They are simply shell commands to run.

The example I have below runs an update-gratitude bash script after the copier template has been rendered.

# copier.yml
num: 128
_answers_file: .gratitude-copier-answers.yml
  - "update-gratitude"

I have put the script in ~/.local/bin so that I know it's always on my $PATH. It will reach back into the copier.yml and update the default number.

# ~/.local/bin/update-gratitude
current=`awk '{print $2}' ~/.copier-templates/gratitude/copier.yml | head -n 1`
new=`expr $current + 1`
echo $current
echo $new
sed -i "s/$current/$new/g" ~/.copier-templates/gratitude/copier.yml