{
  "name": "crud",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "dependencies": {
    "http-server": "^13.0.2",
    "json-server": "^0.17.0",
    "npm-run-all": "^4.1.5"
  },
  "scripts": {
    "serve-http": "http-server",
    "serve-json": "json-server -p 3001 db.json",
    "serve": "npm-run-all serve-*"
  }
}

{
  "name": "crud",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "dependencies": {
    "http-server": "^13.0.2",
    "json-server": "^0.17.0",
    "npm-run-all": "^4.1.5"
  },
  "scripts": {
    "serve-http": "http-server",
    "serve-json": "json-server -p 3001 db.json",
    "serve": "npm-run-all --parallel serve-*"
  }
}

Add parallel flag to yarn
Add parallel flag to yarn
