this derivation will be built:
  /nix/store/qw6p5q7iv477kvnw1lwamlq6gcslxdly-fail-1.drv
building '/nix/store/qw6p5q7iv477kvnw1lwamlq6gcslxdly-fail-1.drv'
fail-1> tribuchet: building on jamie
fail-1> this build is supposed to fail
error: Cannot build '/nix/store/qw6p5q7iv477kvnw1lwamlq6gcslxdly-fail-1.drv'.
       Reason: builder failed with exit code 1.
       Output paths:
         /nix/store/r2zn7yv1rlfg1gnsda7246l4fia55lrp-fail-1
       Last 2 log lines:
       > tribuchet: building on jamie
       > this build is supposed to fail
       For full logs, run:
         nix log /nix/store/qw6p5q7iv477kvnw1lwamlq6gcslxdly-fail-1.drv