Since 1976, storing the basic input/output system software on a separate piece of hardware has been the go-to approach. Standard BIOS firmware contains the first piece of code to run when the device turns on, controlling how the other elements of the device accept input/express output and locating the boot device. The problem is that a traditional BIOS is too slow and insufficiently customizable when designing for embedded systems. There’s no need to copy the standard BIOS when you can instead create your own system. Intel’s Boot Loader Development Kit allows developers to easily create flexible, versatile, as-fast-as-needed boot software, optimized for lightweight embedded systems. This article will walk you through the steps involved in starting your own system and includes a specific exercise using Intel’s BLDK to modify an Unified Extensible Firmware Interface to create a new piece of custom firmware.