Templating languages are ubiquitous across software languages and ecosystems. There are so many to choose from, covering many different use cases and requirements, but have you ever wondered what it takes to build one? Using Shopify’s Liquid as a comparison case, I’m starting a new learning experiment to understand how these tools work and what it takes to implement them. This journey will see us diving into lexers, parsers, compilers, and evaluation, combining data with a template to produce a final document.