The Includes File System is possibly one of the most powerful features in CARL

There's one concept in CARL that takes people a few minutes to get their head around. I want to explain it here because it's also one of the best things about the system once it clicks.

It's called the includes file system.

Every CARL site has a folder of plain text files: your navigation, your footer, your sidebar widgets, your signup form. These files are included in your pages at runtime, meaning every time a visitor loads a page, they get the current version of those files.

The practical result: you edit your navigation once and every single page on your site updates instantly. No regeneration. No cache clearing. No plugin. You save the file and it's live everywhere, immediately.

The same system lets you add entire applications to any page with a single line of PHP. I've used it to add lead marketplace systems, booking forms, calculators, and custom tools to CARL sites. The CMS and your custom business logic live in the same file structure, on your own server, owned completely by you.

The first time you see it, it looks unfamiliar. Ten minutes later it makes complete sense and you start thinking of things you want to build with it.

Has anyone here built something unusual on top of a CMS? Custom tools, calculators, niche applications? I'm curious what people actually need that platforms never seem to provide out of the box.

This type of lead generation is entirely possible in CARL, with just 1 simple INCLUDE.