*Note: if your device is on the latest bootloader version and you flash custom firmware then you will receive a hard fault warning when booting the firmware image. To avoid this issue, just remove the code in startup.s added by [this commit](https://github.com/trezor/trezor-firmware/commit/222c9ea46c7574cb52d4713c481438a32b85e692#diff-178d0ab7c4debbcf430a0fad8fa06a5c).*
## Building for development
If you want to build device firmware, make sure you have the