this derivation will be built:
  /nix/store/6bvblsw23lgnkygywgb373lq5zm4xnvl-fail-2.drv
building '/nix/store/6bvblsw23lgnkygywgb373lq5zm4xnvl-fail-2.drv'
fail-2> tribuchet: building on jamie
fail-2> this build is supposed to fail
error: Cannot build '/nix/store/6bvblsw23lgnkygywgb373lq5zm4xnvl-fail-2.drv'.
       Reason: builder failed with exit code 1.
       Output paths:
         /nix/store/ma5q97xgmz8nfk93pan8sv35yn8cgl6j-fail-2
       Last 2 log lines:
       > tribuchet: building on jamie
       > this build is supposed to fail
       For full logs, run:
         nix log /nix/store/6bvblsw23lgnkygywgb373lq5zm4xnvl-fail-2.drv