staffmanager/database/seeds/NewPermissions.php

<?php

use Illuminate\Database\Seeder;
use Spatie\Permission\Models\Permission;
use Spatie\Permission\Models\Role;

class NewPermissions extends Seeder
{
    /**
     * Run the database seeds.
     *
     * @return void
     */
    public function run()
    {
        $developer = Role::create([
           'name' => 'developer'
        ]);

        $admin = Role::where('name', 'admin')->first();

        Permission::create(['name' => 'admin.settings.view']);
        Permission::create(['name' => 'admin.settings.edit']);

        $developer->givePermissionTo('admin.developertools.use');
        $admin->givePermissionTo('admin.settings.view');
        $admin->givePermissionTo('admin.settings.edit');


    }
}