Eliminating closed source?

[der Mouse <mouse%Rodents-Montreal.ORG@localhost>]

How hard is it to build a kernel without including any closed-source
components?  (For example, most of dev/microcode/, and of course
anything depending on it, would have to go.)

Is there a simple switch I can flip for this, or will I have to just
grovel through all the code eliminating the relevant drivers from the
kernel configs myself?

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