XPath/XSLT 2+ also have only a single implementation
As far as XPath goes, that's wrong:
1. Saxon (the one you talk about)
2. BaseX (an XQuery 3.1 processor)
3. Xidel (implements many XQuery 3.1 features)
4. eXistdb
5. fonto-xpath (NodeJS)
6. frameless.io (JS, also XSL)
And these are the ones, which face the public internet. I think, Microsoft has an 2.x implementation, I am pretty sure, IBM and Oracle do so, as well.
Now, as for XSL-T, you are right: the easily available implementations are Saxon, but, as it seems, also frameless.io (which I just found out about a few minutes ago, so I may be wrong). But again, I guess, that big enterprise has their own solutions bundled.
Comments
As far as XPath goes, that's wrong:
1. Saxon (the one you talk about)
2. BaseX (an XQuery 3.1 processor)
3. Xidel (implements many XQuery 3.1 features)
4. eXistdb
5. fonto-xpath (NodeJS)
6. frameless.io (JS, also XSL)
And these are the ones, which face the public internet. I think, Microsoft has an 2.x implementation, I am pretty sure, IBM and Oracle do so, as well.
Now, as for XSL-T, you are right: the easily available implementations are Saxon, but, as it seems, also frameless.io (which I just found out about a few minutes ago, so I may be wrong). But again, I guess, that big enterprise has their own solutions bundled.