this derivation will be built:
  /nix/store/6fp30dl2qhnxjkc26m40awwpvvl1p8rv-fail-3.drv
building '/nix/store/6fp30dl2qhnxjkc26m40awwpvvl1p8rv-fail-3.drv'
fail-3> tribuchet: building on jamie
fail-3> this build is supposed to fail
error: Cannot build '/nix/store/6fp30dl2qhnxjkc26m40awwpvvl1p8rv-fail-3.drv'.
       Reason: builder failed with exit code 1.
       Output paths:
         /nix/store/bl2pzgl27wphmipx10zklk0943hkvgjj-fail-3
       Last 2 log lines:
       > tribuchet: building on jamie
       > this build is supposed to fail
       For full logs, run:
         nix log /nix/store/6fp30dl2qhnxjkc26m40awwpvvl1p8rv-fail-3.drv