Design principles

This keymap was heavily inspired by Callum's layout for QMK and is guided by the following principles:

1. Every key should have just one way to type it, the only exception is the SHIFT key that is both available as a HR mod behind a layer and a thumb key.

2. Avoid hold-taps as they are finnicky to tweak, could misfire or require long pauses. Same reasons pointed by Callum at his readme apply here. An excecption was made to accomodate GLOBE in both DEF and NAV layers, at the Z key position. This allows me to trigger my window manager of choice (Swish) on macOS as well as use iPadOS shorcuts. There's also a &lt hidden in the NWD layer to allow for triggering SYM form there on hold and cancelling &numword when tapped.

3. Thumbs do all the regular layer changes. Except for &smart_mouse and &numword, that are toggled by combos.

4. Keyboard functionality (such as &bootloader and bluetooth toggles) is hidden behind combos available only in the FUN layer. This makes them purposelly difficult to trigger by accident, while still being still being accessible when needed;

5. Combos should be convenience only, such as:

   • NAV layer toggle for extended edits (left thumb keys);
   • mute (vol up and down on NAV); and
   • left hand activation of some special keys (ENTER, BACKSPACE, SPACE and ESCAPE).

6. Tap dance is used to make double press on thumb shift trigger &caps_word behavior and to combine next song and previous song into the same key on NAV.

My use case and layer design choices

Its main uses are writing prose in both English and Portuguese as well as some very light coding.

1. QWERTY with changes on ' ; and / keys positions

Base layout is QWERTY with a few changes to optimize for my use case.

• On DEF, ; was moved down and made way to ' as this is far more useful to make accents and quotes in my use cases.
• / exists in the SYM layer.

2. Longe &sk timeouts and &lc for cancelling queued mods when triggering other layers

A crazy long timeout (1000m) was assigned to &sk behavior in this keymap. So there's no rush to combine mods with keycodes with keys from DEF or whatever the currently active layer.

Layer keys (usually &mo) were replaced by a custom layer-cancel macro (&lc) that taps a &kp K_CANCEL command alongside the &mo command. This workaround cancels any previoulsy &sk queued mods on the layer key press.

This design allows for canceling mods only when invoking SYM, NAV, of FUN, while still keep them triggered when you move back to DEF.

This emulates in ZMK the LA_NAV and LA_SYM custom behaviors found in Callum's QMK keymap.

It's built with the parametrized macros as &lc to allow for easier reading of the keymap and user modification.

3. &swapper for swapping between apps/windows

Allows for CMD+TAB with just one key. It keeps the modal open until you release the layer toggle, just as you would hold CMD between TAB keypresses.

This is not native to ZMK's main repo and requires PR# 1366. See ZMK.dev documentation for instructions on how to use PRs not yet merged into ZMK's main repo.

4. Numpad for &numword

&numword is accessible via S and D key combo.

This behavior allows for quick entering numbers and will disable the numpad layer upon key press of any key than a number, math symbol or BACKSPACE/DELETE. I believe this behavior was introduced to the custom mech community in QMK by Jonas Hietala. This ZMK implemenation was made by urob and I've copied with a few modifications here.

5. Apple's Globe key on mod-tap Z and ; keys

Recently ZMK implementted a keycode for emulating GLOBE/fn key on Apple's keyboards.

It's not 100% the same behavior made by Apple's keyboards (see limitations here), but it gets the job done for my uses – wich is mainly window manipulation on both macOS and iPadOS. So I've made it into a &mt replicated in DEF, NAV and SYM on the keys used by lower pinkies.

6. &smart_mouse copied from urob's repo

Yet another feature copied from urob's repo.

It is activated from the M,. key combo, from DEF layer.

Also requires PR #1366 used in &swapper behavior.

7. Left hand combos for one handed use of common action keys in combination with the mouse on the right hand

Some combos where added to make it possible to use the keyboard one handed. They're mainly for use with the left hand (so a mouse can be used on the righ hand).

• QA for ESC
• WS for TAB
• ED for F18 (which I use to trigger some app-specific macros on Keyboarad Maestro)
• RF for ENTER
• TG for BACKSPACE