Feedback would be greatly welcome! It's made specifically for the usecase you mention, blog-like website with Katex to add pretty graphics. Example usage:
<!-- Draw a triangle with labels on the sides and angles -->
<vector-graph x="3" y="3" axis="false">
<polygon points="0,0;1,3;3,1" sides="a,b,c" angles="α,β,γ"></polygon>
</vector-graph>
<!-- a + b = c, but in vector form (with lots of labels) -->
<vector-graph x="4.9" y="4.9">
<vector label="b" color="blue" from="3,4" to="4,2" axis></vector>
<vector label="a" color="red" from="0,0" to="3,4" axis></vector>
<vector label="c" from="0,0" to="4,2"></vector>
</vector-graph>
PS, I give you permission to use it in your personal website for free, alexkritchevsky.comEdit: note that the examples in the website, since they are part of the README in Github, are plain SVG images that have been rendered on the backend statically also by VectorGraph, see the Node.js environment if interested: