We currently index the Zephyr project by indexing the Git repo at https://github.com/zephyrproject-rtos/zephyr in Elixir. However, this repo is in fact not standalone: it has references to several other projects. The correct way to get Zephyr is to use "west", which processes https://github.com/zephyrproject-rtos/zephyr/blob/main/west.yml to retrieve all the right repos.

To give an example, the driver drivers/gpio/gpio_nrfx.c in Zephyr itself calls the function nrfx_gpiote_channel_get(), which is nowhere to be found in the Zephyr repo itself. It is in fact implemented in the hal_nordic repo, which gets pulled as a module by west (see https://github.com/zephyrproject-rtos/hal_nordic).