Apache is a free and open-source cross-platform web server software.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
Personio is the all-in-one HR software for small- and medium-sized companies with 10 to 2000 employees.
PHP is a general-purpose scripting language used for web development.
Swiper is a JavaScript library that creates modern touch sliders with hardware-accelerated transitions.