I don't really know what this means, looked through the documentation but all I can workout is that something needs to pass what I assume is 'true' to somewhere else. I took this verbatim from another definition in guix.
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> > - (native-inputs
> > - `(("zlib" ,zlib)
> I think zlib should be an input rather than a native-input since the code
> seems to link to it. Remember that the reason for native-inputs verses
> inputs is that native-inputs are needed on the host side when cross