it is a suite of software for creating virtual-integrated-circuits within field-programmable-gate-arrays ( FPGAs ), for people who want to fake an integrated-circuit, or who want the most-extrememly-fast compiler, or some such thing, hardware-accelerated.

( feel free to paraphrase, no crediting-me obligatory: that gets the sense of it.

I've read that the fastest Haskell compiler ever made was in an FPGA )

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