..tip::

It's recommended to use the `PSR-4`_ autoload standard: use the namespace as key,

and the location of the bundle's main class (relative to ``composer.json``)

as value. As the main class is located in the ``src/`` directory of the bundle:

It's recommended to use the `PSR-4`_ autoload standard on your bundle's

``composer.json`` file. Use the namespace as key, and the location of the

bundle's main class (relative to ``composer.json``) as value. As the main

class is located in the ``src/`` directory of the bundle:

..code-block::json

Developing a Reusable Bundle

Bundles are meant to be reusable pieces of code that live independently from

any particular Symfony application. However, a bundle cannot run on its own: it

must be registered inside an application to execute its code.

This can be a bit challenging during development. When working on a bundle in

its own repository, there's no Symfony application around it, so you need a way

to test your changes inside a real application environment.

There are two common approaches to do this, depending on whether your bundle has

already been published or is still under development.

Using a Local Path Repository

If your bundle hasn't been published yet (for example, it's not available on

Packagist), you can point Composer to your local bundle directory from any

Symfony application you use for testing.

Edit the ``composer.json`` file of your application and add this:

..code-block::json

Then, in your application, install the bundle as usual:

..code-block::terminal

Composer will create a symbolic link (symlink) to your local bundle directory,

so any change you make in the ``AcmeBlogBundle/`` directory is immediately

visible in the application. You can now enable the bundle in ``config/bundles.php``::

This setup is ideal during early development because it allows quick iteration

without publishing or rebuilding archives.

Linking an Already Published Bundle

If your bundle is already public (for example, it's published on Packagist),

you can still develop it locally while testing it inside a Symfony application.

In your application, replace the installed bundle with a symlink to your local

development copy. For example, if your bundle is installed under

``vendor/acme/blog-bundle/`` and your local copy is in ``~/Projects/AcmeBlogBundle/``:

..code-block::terminal

Symfony will now use your local bundle directly. You can edit its code, run

tests, and see the changes immediately. When you're done, restore the vendor

folder or reinstall the package with Composer to go back to the published version.

Learn more