[Nix-dev] What does this build error on Hydra mean?

[Peter Simons]

Hi,

Hydra reported a weird build error at <http://hydra.nixos.org/build/766313>
that I don't know to how to interpret:

 | these derivations will be built:
 |   /nix/store/88n1j765d6fsvchv0l52pajdi2rd2nxf-git-1.7.3.2.drv
 |   /nix/store/j1xiir1538znvrbibczsdhmr6z5bpvxi-subversion-1.6.12.drv
 | building path(s) `/nix/store/q9flmjaflv6048zyr1njk59igzi7b6r4-subversion-1.6.12'
 | error: a `i686-darwin' is required to build `/nix/store/j1xiir1538znvrbibczsdhmr6z5bpvxi-subversion-1.6.12.drv', but I am a `x86_64-linux'

Does anyone know what this means? 

Take care,
Peter