RISC-V International
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Haiku has been ported to RISC-V: https://www.haiku-os.org/blog/kallisti5/2021-11-07_booting_our_risc-v_images/
There is an initial port of Hubris to the Freedom E310 core on a Sparkfun RED-V board: https://github.com/oxidecomputer/hubris/discussions/365
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