tasks.json

{
  // These tasks will run in order when initializing your CodeSandbox project.
  "setupTasks": [],

  // These tasks can be run from CodeSandbox. Running one will open a log in the app.
  "tasks": {
    "dev": {
      "name": "Start Server",
      "command": "npm start",
      "runAtStart": true,
      "preview": {
        "port": 3000
      },
      "restartOn": {
        "files": [
          "./package.json"
        ],
        "branch": false,
        "resume": false
      }
    },
    "build": {
      "name": "Build",
      "command": "npm run build"
    },
    "start": {
      "name": "Start Server",
      "command": "npm start"
    },
    "lint": {
      "name": "Lint",
      "command": "npm run lint"
    },
    "install": {
      "name": "Install Dependencies",
      "command": "npm install",
      "restartOn": {
        "files": [
          "./package.json"
        ],
        "branch": false,
        "resume": false
      }
    }
  }
}