Type Auto-Detection

With type = "auto" (the default), SSI detects each file’s format from its extension and processes it accordingly:

• .html files are included as-is — HTML tags work as written.
• .md files are converted from Markdown to HTML.
• .txt files are plain text, HTML-escaped for safety.

All three file types live in the same mixed-content/ directory and share the same 📦 emoji. This page’s header, body, and footer come from three different files in that directory — and SSI handled each one the right way automatically.

Why auto-detection?

When you’re building a site with a mix of content types, you don’t have to configure a separate include step for each format. One step covers everything.

The plain-text footer

Notice the footer below. It comes from a .txt file, so any HTML in it would be escaped and shown as literal text — useful for content that should never inject markup.