After installation of Gulp: “no command 'gulp' found”

I solved the issue without reinstalling node using the commands below:

$ npm uninstall --global gulp gulp-cli
$ rm /usr/local/share/man/man1/gulp.1
$ npm install --global gulp-cli

That's perfectly normal. If you want gulp-cli available on the command line, you need to install it globally.

npm install --global gulp-cli

See the install instruction.

Also, node_modules/.bin/ isn't in your $PATH. But it is automatically added by npm when running npm scripts (see this blog post for reference).

So you could add scripts to your package.json file:

{
    "name": "your-app",
    "version": "0.0.1",
    "scripts": {
        "gulp": "gulp",
        "minify": "gulp minify"
    }
}

You could then run npm run gulp or npm run minify to launch gulp tasks.