6. SEF files

Processing XML in the browser with only JavaScript is not easy or efficient. That’s one of the reasons for SaxonJS!

This is a chicken-and-egg problem because XSLT stylesheets are XML.

SaxonJS resolves this problem by operating on a compiled version of the XSLT stylesheet: an SEF (Stylesheet Export File).

The XSLT-to-SEF compiler resolves the stylesheet down into something that can be processed efficiently in the browser.