Dactyl Manuform 4x5 — LOTR Themed ZMK Keyboard

A hand-wired, split ergonomic keyboard built on the Dactyl Manuform 4x5 layout, running ZMK firmware on nice!nano controllers. The case is 3D-printed and painted with a Lord of the Rings theme, featuring Elvish script, the White Tree of Gondor, and LOTR keycaps from Drop. The firmware uses home row mods (mod-tap): Shift, Ctrl, Alt, and Gui live on the home row so you hold for the modifier and tap for the letter.

The Build

Internal Wiring

Hand-wired matrix with diodes (col2row), connected to nice!nano controllers via a Pro Micro-compatible pinout.

Specs

Layout	Dactyl Manuform 4x5, split
Keys	46
Home row mods	Mod-tap: Shift/Ctrl/Alt/Gui on A–F and J–;
Matrix	10 columns x 5 rows
Controller	nice!nano v2 (nRF52840)
Firmware	ZMK
Connectivity	Bluetooth (split halves communicate over BLE) + USB
Diode direction	col2row
Case	3D-printed, hand-painted

Keymap

Four layers. The default layer uses home row mods via ZMK’s &mt (mod-tap) behavior: the home row still types letters when tapped, but acts as modifiers when held.

Layer 0 — Default (QWERTY)

 ┌─────┬─────┬─────┬─────┬─────┐               ┌─────┬─────┬─────┬─────┬─────┐
 │  Q  │  W  │  E  │  R  │  T  │               │  Y  │  U  │  I  │  O  │  P  │
 ├─────┼─────┼─────┼─────┼─────┤               ├─────┼─────┼─────┼─────┼─────┤
 │SH/A │CT/S │AL/D │GU/F │  G  │               │  H  │GU/J │AL/K │CT/L │SH/; │
 ├─────┼─────┼─────┼─────┼─────┤               ├─────┼─────┼─────┼─────┼─────┤
 │  Z  │  X  │  C  │  V  │  B  │               │  N  │  M  │  ,  │  .  │  /  │
 └─────┴─────┼─────┼─────┼─────┘               └─────┼─────┼─────┼─────┴─────┘
             │  [  │  ]  │                             │  -  │  =  │
             └─────┴─────┘                             └─────┴─────┘
                   ┌─────┬─────┐           ┌─────┬─────┐
                   │SPACE│ TAB │           │BSPC │SPACE│
                   ├─────┼─────┤           ├─────┼─────┤
                   │RAISE│LOWER│           │LOWER│RAISE│
                   ├─────┼─────┤           ├─────┼─────┤
                   │ADJST│ ESC │           │ENTER│ADJST│
                   └─────┴─────┘           └─────┴─────┘

Home-row mods use balanced flavor (280ms tapping term, 75ms quick-tap).

Layer 1 — Lower (Navigation & Media)

Arrow keys, Home/End, Page Up/Down, volume, and media controls.

Layer 2 — Raise (Numbers & Symbols)

! @ # $ % ^ & * ( ) on the top row, 1–0 on the home row, plus ' and \.

Layer 3 — Adjust (System)

Bluetooth profile selection (0–4), BT clear, USB/BLE output toggle, mouse movement and clicks, and the Globe key.

Firmware

Built with the ZMK user config pattern. GitHub Actions compiles the firmware automatically on every push.

Building

Push to the main branch (or open a PR) and GitHub Actions will produce a firmware artifact containing .uf2 files for both halves:

• dactyl_manuform_left-nice_nano.uf2
• dactyl_manuform_right-nice_nano.uf2
• settings_reset-nice_nano.uf2

Flashing

1. Put the nice!nano into bootloader mode (double-tap reset).
2. Copy the appropriate .uf2 file to the mounted drive.
3. Flash the left half first (it's the central/host side).

Project Structure

├── .github/workflows/build.yml    # CI workflow
├── boards/shields/dactyl_manuform
│   ├── dactyl_manuform.dtsi        # Matrix & key transform
│   ├── dactyl_manuform.keymap      # Keymap & layers
│   ├── dactyl_manuform.zmk.yml     # Shield metadata
│   ├── dactyl_manuform_left.overlay
│   ├── dactyl_manuform_right.overlay
│   ├── Kconfig.defconfig
│   └── Kconfig.shield
├── config
│   ├── dactyl_manuform.conf        # Firmware config options
│   └── west.yml                    # ZMK manifest
├── zephyr/module.yml
├── build.yaml                      # Build matrix
└── images/                         # Build photos

Credits

• Case design based on the Dactyl Manuform
• Firmware powered by ZMK
• Controller: nice!nano