Hello,
I am using React on the Front-end, every time i made the changes it does not automatically build. I always type build brunch on the assets folder.

this is my brunch.config.js

exports.config = {
// See Brunch - ultra-fast HTML5 build tool for docs.
files: {
javascripts: {
joinTo: “js/app.js”

  // To use a separate vendor.js bundle, specify two files path
  // http://brunch.io/docs/config#-files-
  // joinTo: {
  //   "js/app.js": /^js/,
  //   "js/vendor.js": /^(?!js)/
  // }
  //
  // To change the order of concatenation of files, explicitly mention here
  // order: {
  //   before: [
  //     "vendor/js/jquery-2.1.1.js",
  //     "vendor/js/bootstrap.min.js"
  //   ]
  // }
},
stylesheets: {
  joinTo: "css/app.css"
},
templates: {
  joinTo: "js/app.js"
}

},

conventions: {
// This option sets where we should place non-css and non-js assets in.
// By default, we set this to “/assets/static”. Files in this directory
// will be copied to paths.public, which is “priv/static” by default.
assets: /^(static)/
},

// Phoenix paths configuration
paths: {
// Dependencies and current project directories to watch
watched: [“static”, “css”, “js”, “vendor”],
// Where to compile files to
public: “../priv/static”
},

// Configure your plugins
plugins: {
babel: {
presets: [“es2015”, “react”],
// Do not use ES6 compiler in vendor code
ignore: [/web/static/vendor/]
}
},

modules: {
autoRequire: {
“js/app.js”: [“js/app”]
}
},

npm: {
enabled: true,
whitelist: [“phoenix”, “phoenix_html”, “react”, “react-dom”]
}
};

Package.json

{
“repository”: {},
“license”: “MIT”,
“scripts”: {
“deploy”: “brunch build --production”,
“watch”: “brunch watch --stdin”
},
“dependencies”: {
“axios”: “^0.17.0”,
“babel-preset-react”: “^6.24.1”,
“phoenix”: “file:../deps/phoenix”,
“phoenix_html”: “file:../deps/phoenix_html”,
“react”: “^16.0.0”,
“react-dom”: “^16.0.0”,
“react-router-dom”: “^4.2.2”
},
“devDependencies”: {
“babel-brunch”: “6.1.1”,
“brunch”: “2.10.9”,
“clean-css-brunch”: “2.10.0”,
“uglify-js-brunch”: “2.10.0”
}
}