Question: w/r/t your education research deliverables, I'd be interested to hear more about that solution's implementation... Thinking we are headed down the same path, but for the purpose of producing large, customized downloadable books. Using PDFlib right now but I believe that will take its toll at scale.
Last things first: having another layer before LaTeX -> PDF would - in my eyes - not make LaTeX any better but increase the bloat. But this is just a spontaneous opinion.
About PDFlib I'd just like to add that a commercial (non-OSS) product with a lot of language bindings is hardly a solution for a problem which obviously should be solved using a domain specific language.
We are currently still using LaTeX but are always looking to migrate to something else. HTML is our favorite but not the winner.
But, I'd still like to hear more about how you use LaTeX in your solution.
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