# zmkfirmware/zmk

ZMK Firmware Repository

Repository: https://github.com/zmkfirmware/zmk
Canonical: https://ross.abutalabs.com/products/zmk
Homepage: https://zmk.dev/
Language: C
License: MIT
License Family: permissive
Topics: zmk, mechanical-keyboard, zephyr, bluetooth, wireless, hacktoberfest, keyboard, keyboard-firmware
Last push: 2026-08-25T05:03:32+00:00

## Health v2 (maintenance only)
Score: 75/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 29, longevity 100
- inputs: {"age_days": 2277, "days_push": 8, "days_rel": 397, "gap_med": 86, "n_releases_24m": 4}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4239, forks 4116 (observed 2026-08-28T04:08:39.585496+00:00)

## What it is
ZMK Firmware is an open source (MIT) keyboard firmware built on the Zephyr RTOS, designed for modern wireless (BLE) and wired mechanical keyboards. It is a clean-room implementation offering keymaps, layers, hold-taps, combos, macros, and broad 32-bit microcontroller support.

## Use cases
- flash custom firmware for a wireless split mechanical keyboard
- configure keymaps with layers, combos, and mod-taps
- build low-power BLE keyboard firmware for a 32-bit MCU
- find an MIT-licensed alternative to QMK
- set up multi-device Bluetooth keyboard connectivity
- add rotary encoders or displays to a custom keyboard

## When to choose
- you need wireless/BLE keyboard support with low power usage
- you want permissive MIT licensing instead of GPL
- you use modern 32-bit ARM/RISC-V microcontrollers
- you want advanced keymap features like hold-taps, combos, and macros

## When to avoid
- your keyboard uses AVR/8-bit chips like ATmega32U4
- you rely on QMK's ecosystem or existing QMK keymaps without porting
- you need wired split keyboard support, which is still under development

## Facets
- artifact type: application
- maturity: active
- function: embedded, configuration-management
- domain: embedded-systems, hardware, cross-platform
- platform: embedded, iot, c
- tags: keyboard-firmware, zephyr-rtos, mechanical-keyboard, wireless, ble, split-keyboards, qmk-alternative, bluetooth

## Member repositories
- zmkfirmware/zmk (main) score 75

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:39.585496+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T18:22:16.229317+00:00, confidence not recorded.
  - readme: https://github.com/zmkfirmware/zmk (fetched 2026-08-28T04:08:39.585496+00:00, sha b1743bc97fd8)
  - homepage: https://zmk.dev/ (fetched 2026-08-29T09:12:07.793733+00:00, sha d01bfd6bcfef)
  - site_page: https://zmk.dev/docs (fetched 2026-08-29T09:12:07.797089+00:00, sha d385927f7971)
  - site_page: https://v0-3-branch.zmk.dev/docs (fetched 2026-08-29T09:12:07.799406+00:00, sha 437df88c7a42)
  - site_page: https://zmk.dev/docs/development/contributing/clean-room (fetched 2026-08-29T09:12:07.801991+00:00, sha 5659bbbb9670)
- Data as of 2026-08-30T08:39:29.467469+00:00.