Recomendation for running SASS watch?

[carcinocron]

This is my sentry file, it works really well for watching a dev http server while concurrently running sass --watch. But my sentry config for sass is probably running it twice. Any recommended changes?

require "sentry"

sentry = Sentry::ProcessRunner.new(
    display_name:   "app",
    build_command:          "crystal build ./src/app.cr",
    run_command:            "./app",
    # build_args:     [] of String,
    # run_args:       [] of String,
    files: ["./src/**/*.cr", "./src/views/**/*.ecr"],
    should_build: true,
    install_shards: false,
    colorize: true,
)

spawn {
  Sentry::ProcessRunner.new(
    display_name:   "sass",
    build_command:          "node_modules/.bin/sass",
    run_command:            "node_modules/.bin/sass",
    build_args:       ["./src/sass/main.sass:./public/css/one.css"],
    run_args:       ["./src/sass/main.sass:./public/css/one.css"],
    files: ["./src/sass/**/*.sass", "./src/sass/**/*.css"],
    should_build: true,
    install_shards: false,
    colorize: true,
  ).run
}

sentry.run