I created a small project called GraphXML. It uses an XML-based format to define charts and renders them using C + SDL2.

It can produce line and bar charts and export them directly to PNG without opening a window, which is handy for scripts or Termux setups.

The syntax is simple and easy to read. There are plans to add FFI support for Python and JavaScript/WebAssembly, which could make it easier to use in other projects.

The repository includes examples and a demo PNG: https://github.com/Ferki-git-creator/graphxml

It could be useful for people looking for a lightweight, programmatic way to create charts.