The open source alternative to BIOS and UEFI, coreboot is often praised for its speed and security [1]. However, just as important is the accessibility of its firmware. According to the coreboot website, "The architecture of coreboot is designed to have an unbrickable update process. Updating firmware should be no more dangerous than installing your favorite app on your mobile phone." As the major result of this goal, users can choose to customize their own firmware. Much like customizing the Linux kernel, the process is lengthy but mostly a matter of following instructions in the thorough documentation. Although the documentation is oriented towards Debian, it can easily be transposed to other distributions, the main difference being the occasional difference in the names of some of the necessary packages.

You may want to build your own firmware for several reasons. You might want to install coreboot on a machine that already has its own BIOS or UEFI. If your machine already uses coreboot, you might want to tweak it to better suit your needs. For example, you may prefer to turn off virtualization support in order to get every bit of performance from your machine. Sometimes, too, an unsupported mainboard might be usable with a few experimental tweaks. Perhaps the main reason is that building coreboot firmware can satisfy your curiosity about a technology that is still unfamiliar to most Linux users.

Despite the project's goals, some chance exists that you could brick your machine. Should that happen, another attempt at coreboot customization or the manufacturer's firmware may restore functionality. All the same, before flashing your custom firmware, you should make sure you have a current backup and thoroughly research what you are doing before you begin.

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