how i can create my library in codeigniter 4

this is easy in codeigniter 3 but i cant find this in codeigniter 4 document

It is even easier than V3. The only tricky bit is learning to use namespace.

Here's a very simple library

app/Libraries/MyCustomClass.php

PHP Code:

<?php namespace App\Libraries;

class MyCustomClass
{
 public function sayHi()
 {
 return "Hello World!";
 }
} 


Here's a simple example of using the custom library in a controller.

PHP Code:

<?php namespace App\Controllers;

use App\Libraries\MyCustomClass;  //so we can easily load the custom library

class Home extends BaseController
{
 public function index()
 {
 $mine = new MyCustomClass(); // loads and creates instance
 echo $mine->sayHi();
 }
}