Dynamic user content in Rails with Liquid tags

When building features that accept user-generated content, you may need to display dynamic content based on what the user specifies. Imagine you want to users to be able to customize a welcome message sent from your application when they invite someone to their account.Rails programmers are deeply familiar with writing content with pieces of dynamic text: we do this all the time when writing view templates. But we don’t want to allow users to write ERB or HAML strings and execute them in our app. It’s both a huge security risk and also not super friendly for users to have to learn a complete programming language to change some text.