laravel 5 use env variable in blade
Five most important commands if your Laravel is not working as expected after
some modifications in .env or database folder or because of any other modifications.
Here is full explanation: https://www.youtube.com/watch?v=Q1ynDMC8UGg
php artisan config:clear
php artisan cache:clear
composer dump-autoload
php artisan view:clear
php artisan route:clear
After clearup, try "echo env('URL_BUILDER')"