Well, the author thanks the Mame and Mess team here:

14 Credits
# MAME & MESS Team: For info on many chips

See: Xe User Manual

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> How long has Xe been is development, and where on earth did it come from?
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> Is there source code as well?
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> This project looks massive! It is based off MESS or something?
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> Emulation is the sincerest form of flattery
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