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Larva mk.3

Grezeh's Larva keyboard is a Katana style symmetric layout with combined Latin+Cyrillic keymap in mind.
Published March 2, 2024
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While the original Larva, designed by grezeh, is almost 3 years old, version 3 of the PCB of this Katana style symmetric keyboard was released just a few weeks ago.

Designed as part of a personal platform for research of combined, adaptable, extended Latin+Cyrillic keymap, it offers better ergonomics for day-to-day use when typing in multiple languages.

Keyboards, keymap, layouts are developed concurrently, work in symbiosis. I name the whole research project "mnemoNИk|Kombine" – grezeh.

The Larva PCB fits into the daisy 40% hhkb keyboard case by Kprepublic (coupon). The Mk.3 PCB outline is smaller, so it also fits the Poseidon/PSD40 case.


  • Larva mk1 has 4 through-hole LED positions, no RGB, uses *AU MCU.
  • Mk2 has 2 extra RGB SMD LED slots with up-facing SK6812MINI-E LEDs and 2 mono-color SMD LEDs, as well as "a few small QoL improvements".
  • Mk2.1-light version gets rid of RGB and went open-source.
  • Mk3: smaller outline to fit the PSD40 case, added one more bottom row option and non-stab option (without ISO enter).


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Published on Sat 2nd Mar 2024. Featured in KBD #157.



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