I developed xjslt, an XSLT 2.0 (https://www.w3.org/TR/xslt20/) compiler for JavaScript. XSLT is still the best way to transform XML content into other XML or HTML content, and there is only one generally available 2.0 or later version, Saxon. Saxon is an excellent piece of software, but SaxonJS is not open source and I thought it might be good to have another option.

There is a simple command line interface as well as the ability to compile to a standalone JavaScript file for loading in a browser and to a JavaScript file that can be used in NodeJS and other JavaScript runtimes. This means you can run your XSLT transforms on the server or in a cloud function.

The majority of functionality is in place and it has worked with many XSLT files I have tried. There are a number of incomplete and/or broken features. The speed is very reasonable.