this derivation will be built:
  /nix/store/hksaj3y760ln3s3wgjascxg0xqxx78za-spec-shfmt.drv
building '/nix/store/hksaj3y760ln3s3wgjascxg0xqxx78za-spec-shfmt.drv' on 'grpc://farm.numtide.com:50051?connect-timeout=20&system=aarch64-darwin&token-file=/run/nix-farm-client/farm-token'
building '/nix/store/hksaj3y760ln3s3wgjascxg0xqxx78za-spec-shfmt.drv' on farm.numtide.com:50051
spec-shfmt> mac02: building hksaj3y760ln3s3wgjascxg0xqxx78za-spec-shfmt.drv
spec-shfmt> invalid/a.sh:1:10: `then` must be followed by a statement list
spec-shfmt> invalid/a.sh:1:10: `then` must be followed by a statement list