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. LUFA, ChibiOS, or imported files from other repositories etc.)
- if there is valid 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.
- no "old-school" or other low-level GPIO/I2C/SPI functions may be used -- must use QMK abstractions unless justifiable (and laziness is not valid justification)
-`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
- 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
- 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...
- 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
- Do not include VIA json files in the PR. These do not belong in the QMK repository as they are not used by QMK firmware -- they belong in the [VIA Keyboard Repo](https://github.com/the-via/keyboards)
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.
In general, we want to see two (or more) approvals that are meaningful (e.g. that have inspected code) before a PR will be considered for merge. These reviews are not limited to collaborators -- any community member willing to put in the time is welcomed (and encouraged). The only difference is that your checkmark won't be green, and that's fine!
Additionally, PR reviews are something that is done in our free time. We are not paid nor compensated for the time we spend reviewing, as it is a labor of love. As such, this means that it can take time for us to get to your Pull Request. Things like family, or life can get in the way of us getting to PRs, and burnout is a serious concern. The QMK firmware repository averages 200 PRs opened and 200 PRs merged every month, so please have patience.