Before deploying your CodeIgniter application to production, there are several things you can do to make your application run more efficiently.

This section describes the optimization features that CodeIgniter provides.

spark optimize

Added in version 4.5.0.

The spark optimize command performs the following optimizations:

Composer Optimization

Removing Dev Packages

When you deploy, don’t forget to run the following command:

composer install --no-dev

The above command will remove the Composer packages only for development that are not needed in the production environment. This will greatly reduce the vendor folder size.

Specifying Packages to Discover

If Composer Package Auto-Discovery is enabled, all Composer packages are scanned when needed. But there is no need to scan packages that are not CodeIgniter packages, so specifying the packages to be scanned prevents unnecessary scanning.

See Specify Composer Packages.

Config Caching


Once cached, configuration values are never changed until the cache is deleted, even if the configuration file or .env is changed.

Caching the Config objects can improve performance. However, the cache must be manually deleted when changing Config values.

See Config Caching.

FileLocator Caching

Caching the file paths that FileLocator found can improve performance. However, the cache must be manually deleted when adding/deleting/changing file paths.

See FileLocator Caching.

PHP Preloading

With PHP preloading, you can instruct the server to load essential files like functions and classes into memory during startup. This means these elements are readily available for all requests, skipping the usual loading process and boosting your application’s performance. However, this comes at the cost of increased memory usage and requires restarting the PHP engine for changes to take effect.


If you want to use Preloading, we provide a preload script.


Using preloading requires one dedicated PHP handler. Normally, web servers are configured to use one PHP handler, so one app requires a dedicated web server. If you want to use preloading for multiple apps on one web server, configure your server to use virtual hosts with multiple PHP handlers like multiple PHP-FPMs, with each virtual host using one PHP handler. Preloading keeps the relevant definitions in memory by reading the files specified in opcache.preload.


See Running Multiple Applications with one CodeIgniter Installation to make one core CodeIgniter4 to handle your multiple apps.


Open php.ini or xx-opcache.ini if you have split INI configuration in PHP, and recommend to set opcache.preload=/path/to/preload.php and opcache.preload_user=myuser.


myuser is user running in your web server. If you want to find the location of the split INI configuration, just run php --ini or open file phpinfo() and search Additional .ini files parsed.

Make sure you use the appstarter installation. If using manual installation, you must change the directory in include path.


// ...

class preload
     * @var array Paths to preload.
    private array $paths = [
            'include' => __DIR__ . '/system', // <== change this line to where CI is installed
            // ...

    // ...

// ...

Deployment to Shared Hosting Services


index.php is no longer in the root of the project! It has been moved inside the public folder, for better security and separation of components.

This means that you should configure your web server to “point” to your project’s public folder, and not to the project root.

Specifying the Document Root

The best way is to set the document root to the public folder in the server configuration:

└── (project folder)
    └── public/  (document root)

Check with your hosting service provider to see if you can change the document root. Unfortunately, if you cannot change the document root, go to the next way.

Using Two Directories

The second way is to use two directories, and adjust the path. One is for the application and the other is the default document root.

Upload the contents of the public folder to public_html (the default document root) and the other files to the directory for the application:

├── (for the application)
       ├── app/
       ├── vendor/ (or system/)
       └── writable/
└── public_html/ (the default document root)
        ├── .htaccess
        ├── favicon.ico
        ├── index.php
        └── robots.txt

See Install CodeIgniter 4 on Shared Hosting (cPanel) for details.

Adding .htaccess

The last resort is to add .htaccess to the project root.

It is not recommended that you place the project folder in the document root. However, if you have no other choice, you can use this.

Place your project folder as follows, where public_html is the document root, and create the .htaccess file:

└── public_html/     (the default document root)
    └── (project folder)
        ├── .htaccess
        └── public/

And edit .htaccess as follows:

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteRule ^(.*)$ public/$1 [L]

<FilesMatch "^\.">
    Require all denied
    Satisfy All

And remove the redirect settings in public/.htaccess:

--- a/public/.htaccess
+++ b/public/.htaccess
@@ -16,16 +16,6 @@ Options -Indexes
    # RewriteBase /

-   # Redirect Trailing Slashes...
-   RewriteCond %{REQUEST_FILENAME} !-d
-   RewriteCond %{REQUEST_URI} (.+)/$
-   RewriteRule ^ %1 [L,R=301]
-   # Rewrite " ->"
-   RewriteCond %{HTTPS} !=on
-   RewriteCond %{HTTP_HOST} ^www\.(.+)$ [NC]
-   RewriteRule ^ http://%1%{REQUEST_URI} [R=301,L]
    # Checks to see if the user is attempting to access a valid file,
    # such as an image or css document, if this isn't true it sends the
    # request to the front controller, index.php