libctemplate

This is a C library for generating HTML pages dynamically using templates. Instead of writing HTML strings directly in your C code, you'd write separate template files with placeholders, then feed them data from your program. The library fills in those placeholders and outputs the final HTML.

The core idea is separation of concern: your C code handles business logic and data, while template files handle how that data gets formatted into HTML. This makes code cleaner and lets designers or non-programmers edit templates without touching the C code itself.

You'd use this if you're building a web server, API, or any C application that needs to generate HTML pages. For example, if you're writing a backend service, instead of concatenating HTML strings in C, you'd write a template file with placeholders like {name} and {email}, then pass your data to libctemplate, which substitutes the values and gives you finished HTML to send to a browser.

The library was originally created at the University of Virginia and released as open source. However, the author no longer actively maintains or uses it—they've moved to a different templating library called libflate, which they believe has a more user-friendly syntax. The README explicitly suggests newcomers check out libflate instead if they're looking for an HTML templating solution in C. This repository remains available as historical or archived code, but active development and recommendations have shifted elsewhere.