Laravel Cache Auth::user(). Learn how to cache the logged in user at https://paulund.co.uk/laravel-cache-authuser

AppServiceProvider.php

<?php

namespace App\Providers;

use App\Models\User;
use App\Observers\UserObserver;
use Illuminate\Support\ServiceProvider;

class AppServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        User::observe(UserObserver::class);
    }

    /**
     * Register any application services.
     *
     * @return void
     */
    public function register()
    {
        //
    }
}

auth.php

// Config/auth.php
'providers' => [
        'users' => [
            'driver' => 'cache-user',
            'model' => App\Models\User::class,
        ]
    ]

AuthServiceProvider.php

<?php

namespace App\Providers;

use App\Auth\CacheUserProvider;
use Illuminate\Support\Facades\Auth;
use Illuminate\Foundation\Support\Providers\AuthServiceProvider as ServiceProvider;

class AuthServiceProvider extends ServiceProvider
{
    /**
     * The policy mappings for the application.
     *
     * @var array
     */
    protected $policies = [

    ];

    /**
     * Register any authentication / authorization services.
     *
     * @return void
     */
    public function boot()
    {
        // Caching user
        Auth::provider('cache-user', function() {
            return resolve(CacheUserProvider::class);
        });
    }
}

CacheUserProvider.php

<?php

namespace App\Auth;

use App\Models\User;
use Illuminate\Auth\EloquentUserProvider;
use Illuminate\Contracts\Hashing\Hasher as HasherContract;
use Illuminate\Support\Facades\Cache;

/**
 * Class CacheUserProvider
 * @package App\Auth
 */
class CacheUserProvider extends EloquentUserProvider
{
    /**
     * CacheUserProvider constructor.
     * @param HasherContract $hasher
     */
    public function __construct(HasherContract $hasher)
    {
        parent::__construct($hasher, User::class);
    }

    /**
     * @param mixed $identifier
     * @return \Illuminate\Contracts\Auth\Authenticatable|null
     */
    public function retrieveById($identifier)
    {
        return Cache::get("user.$identifier") ?? parent::retrieveById($identifier);
    }
}

UserObserver.php

<?php
namespace App\Observers;

use Illuminate\Foundation\Auth\User;
use Illuminate\Support\Facades\Cache;

/**
 * User observer
 */
class UserObserver
{
    /**
     * @param User $user
     */
    public function saved(User $user)
    {
        Cache::put("user.{$user->id}", $user, 60);
    }

    /**
     * @param User $user
     */
    public function deleted(User $user)
    {
        Cache::forget("user.{$user->id}");
    }

    /**
     * @param User $user
     */
    public function restored(User $user)
    {
        Cache::put("user.{$user->id}", $user, 60);
    }

    /**
     * @param User $user
     */
    public function retrieved(User $user)
    {
        Cache::add("user.{$user->id}", $user, 60);
    }
}

CacheUserProvider
Line number 31 should be.

    /**
     * @param mixed $identifier
     * @return \Illuminate\Contracts\Auth\Authenticatable|null
     */
    public function retrieveById($identifier)
    {
        return Cache::get("user.$identifier") ?? parent::retrieveById($identifier); // here little Type
    }