If there are any inconsistencies with these recommendations, you're best off [creating an issue](https://github.com/qmk/qmk_firmware/issues/new) against this document, or getting in touch with a QMK Collaborator on [Discord](https://discord.gg/Uq7gcHh).
- this does not mean you target a different branch for your PR, rather that you're not working out of your own master branch
- if submitter _does_ use their own `master` branch, they'll be given a link to the ["how to git"](https://docs.qmk.fm/#/newbs_git_using_your_master_branch) page after merging -- (end of this document will contain the contents of the message)
- newly-added directories and filenames must be lowercase
- this rule may be relaxed if upstream sources originally had uppercase characters (e.g. ChibiOS, or imported files from other repositories etc.)
- if there is enough justification (i.e. consistency with existing core files etc.) this can be relaxed
- other licenses are permitted, however they must be GPL-compatible and must allow for redistribution. Using a different license will almost certainly delay a PR getting merged.
- QMK Codebase "best practices" followed
- this is not an exhaustive list, and will likely get amended as time goes by
-`wait_ms()` instead of `_delay_ms()` (remove `#include <util/delay.h>` too)
-`timer_read()` and `timer_read32()` etc. -- see [timer.h](https://github.com/qmk/qmk_firmware/blob/master/tmk_core/common/timer.h) for the timing APIs
- displays correctly in Configurator (press Ctrl+Shift+I to preview local file, turn on fast input to verify ordering)
-`readme.md`
- standard template should be present
- flash command has `:flash` at end
- valid hardware availability link (unless handwired) -- private groupbuys are okay, but one-off prototypes will be questioned. If open-source, a link to files should be provided.
- no `(-/+size)` comments related to enabling features
- remove the list of alternate bootloaders if one has been specified
- no re-definitions of the default MCU parameters if same value, when compared to the equivalent MCU in [mcu_selection.mk](https://github.com/qmk/qmk_firmware/blob/master/quantum/mcu_selection.mk)
- don't repeat `MANUFACTURER` in the `PRODUCT` value
- no `#define DESCRIPTION`
- no Magic Key Options, MIDI Options or HD44780 configuration
- user preference configurable `#define`s need to be moved to keymap `config.h`
- "`DEBOUNCE`" instead of "`DEBOUNCING_DELAY`"
- bare minimum required code for a board to boot into QMK should be present
- initialisation code for the matrix and critical devices
- mirroring existing functionality of a commercial board (like custom keycodes and special animations etc.) should be handled through non-`default` keymaps
-`keyboard.c`
- empty `xxxx_xxxx_kb()` or other weak-defined default implemented functions removed
- commented-out functions removed too
-`matrix_init_board()` etc. migrated to `keyboard_pre_init_kb()`, see: [keyboard_pre_init*](https://docs.qmk.fm/#/custom_quantum_functions?id=keyboard_pre_init_-function-documentation)
- prefer `CUSTOM_MATRIX = lite` if custom matrix used, allows for standard debounce, see [custom matrix 'lite'](https://docs.qmk.fm/#/custom_matrix?id=lite)
- prefer LED indicator [Configuration Options](https://docs.qmk.fm/#/feature_led_indicators?id=configuration-options) to custom `led_update_*()` implementations where possible
- if using `MO(_LOWER)` and `MO(_RAISE)` keycodes or equivalent, and the keymap has an adjust layer when holding both keys -- if the keymap has no "direct-to-adjust" keycode (such as `MO(_ADJUST)`) then you should prefer to write...
...instead of manually handling `layer_on()`, `update_tri_layer()` inside the keymap's `process_record_user()`.
- default (and via) keymaps should be "pristine"
- bare minimum to be used as a "clean slate" for another user to develop their own user-specific keymap
- standard layouts preferred in these keymaps, if possible
- submitters can have a personal (or bells-and-whistles) keymap showcasing capabilities in the same PR but it shouldn't be embedded in the 'default' keymap
- submitters can also have a "manufacturer-matching" keymap that mirrors existing functionality of the commercial product, if porting an existing board
For when people use their own `master` branch, post this after merge:
```
For future reference, we recommend against committing to your `master` branch as you've done here, because pull requests from modified `master` branches can make it more difficult to keep your QMK fork updated. It is highly recommended for QMK development – regardless of what is being done or where – to keep your master updated, but **NEVER** commit to it. Instead, do all your changes in a branch (branches are basically free in Git) and issue PRs from your branches when you're developing.
There are instructions on how to keep your fork updated here:
[**Best Practices: Your Fork's Master: Update Often, Commit Never**](https://docs.qmk.fm/#/newbs_git_using_your_master_branch)
[Fixing Your Branch](https://docs.qmk.fm/#/newbs_git_resynchronize_a_branch) will walk you through fixing up your `master` branch moving forward. If you need any help with this just ask.