# Build ## Install zephyr SDK > See [INSTALL.md](INSTALL.md) for installing the SDK. ## Build the app without MCUboot ```bash source ../env.sh west build -p -b nrf52840_qalmari ``` ## Build everything ```bash source ../env.sh west build -p -b nrf52840_qalmari --sysbuild ``` ## Generate your own key for MCUboot ```bash openssl genrsa -out key.pem 2048 ``` ## Flash the binary to the device > See [FLASH.md](FLASH.md) for installing the app to the device.