I'm surprised no one mentioned https://github.com/pumpkin-mc/pumpkin in this thread. It's the fastest Minecraft server implementation and it's written in Rust.
Yes. Although many document generation SaaS platforms are not transparent about their pricing, they often charge a few cents per document. This is somewhat unacceptable given that the marginal cost is almost zero.
If generating PDF dynamically is what you really care about, consider Typst. https://typst.app/
We use it in production to generate reports, and it is amazing.
Most of the documents are generated in an instant, plus we deployed this on Kubernetes with HPA, so high load isn't an issue.
The main issue I found with an HTML-based approach is that browsers are not designed for papers. It would be very challenging, but still possible [1], to customize the page layout, headers, and footers. Nonetheless, we have even more advanced use cases that only Typst/LaTex could cater to, such as displaying the table header of a table that spans multiple pages on every page.
We [1] have been using Typst to generate PDF documents in production for a few months, such as invoices and labels. It's generating thousands of documents daily, and I'm glad that some of them are printed and used by people in the warehouse who are doing real work.
I really like the simple syntax that Typst provides. It would be much harder for the PMs to edit the templates if we went with other solutions, such as wkhtmltopdf.
We also looked into other document generation services that provide a WYSIWYG interface, and they are all quite expensive and often lack advanced scripting capabilities.