getting a weird error when I try to build project on droplet

On my development environment I would usually run these commands to rebuild my project:

php artisan cache:clear
composer dump-autoload

but when I try running them on my droplet I get some weird errors:

PHP Fatal error:  Uncaught Error: Class 'Illuminate\Foundation\Application' not found in /var/www/dev.drmanansala.com/bootstrap/app.php:14
Stack trace:
#0 /var/www/dev.drmanansala.com/artisan(18): require_once()
#1 {main}
  thrown in /var/www/dev.drmanansala.com/bootstrap/app.php on line 14
Cannot create cache directory /home/francis/.cache/composer/repo/https---packagist.org/, or directory is not writable. Proceeding without cache
Cannot create cache directory /home/francis/.cache/composer/files/, or directory is not writable. Proceeding without cache
Generating autoload files

Anyone have any idea’s whats going on? Also, I can’t seem to get gulp to work on my ubuntu machine. Says gulp is not a command