The present disclosure is directed to flexible bootstrap code architecture. A device may comprise equipment for operating the device and an operating system (OS) for operating the equipment. A boot module may also be included in the device to execute boot operations. At least one flexible boot (FB) module in the boot module may interact with the equipment and/or OS during the boot operations to cause the boot operations to become device-specific. An example boot module may comprise a plurality of FB modules. An example FB module may verify a device/chipset identification and may control the boot operations based on the identification. Other example FB modules may select resources to load based on an OS type, may provide a boot configuration table location for use in OS runtime boot configuration or may load variables from a preload variable directory for use in configuring boot operations.