Mike Slinn


Published 2020-10-03. Last modified 2023-05-18.
Time to read: 1 minutes.

This page is part of the jekyll_plugins collection.

jekyll_eval_filter contains a Liquid filter called evaluate that returns the result of evaluating a Ruby expression.


This filter can evaluation any Ruby expression. No limitations are imposed.

If you use this filter, only allow trusted and verified people to edit the source of your Jekyll website.

With great power comes great responsibility.


{{ "1 + 2" | evaluate }} returns 3

The following potentially destroys your system:

{{ 'sudo rm -rf /' | evaluate }}

On a clear disk you can seek forever.


Add the following highlighted line to your Jekyll project's Gemfile, within the jekyll_plugins group:

group :jekyll_plugins do 
  gem 'jekyll_eval_filter'

And then execute:

$ bundle

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