IMPORTANT NOTE: Drupal 7 is Extended life support until Jan 2025 - unless you need Drupal 7, Drupal users are strongly advised use Drupal 9 instead, or better still Drupal 10.
Drupal is an open source content management platform licensed under the GPL. Equipped with a powerful blend of features, Drupal can support a variety of websites ranging from personal blogs, corporate brochures and large community-driven websites.

Jenkins is an award-winning application that monitors executions of repeated jobs, such as building a software project or jobs run by cron. Among those things, current Jenkins focuses on building/testing software projects continuously (e.g., like CruiseControl) and monitoring executions of externally-run jobs.

Ruby on Rails is an open-source web framework that's optimized for programmer happiness and sustainable productivity. Written in Ruby, Rails lets you write beautiful code by favoring convention over configuration. The result is a web framework that allows you to transition from idea to implementation in a very short period of time.

Ansible is a simple, agentless IT automation engine that automates cloud provisioning, configuration management, application deployment and intra-service ochestration. It can configure systems, deploy software, and streamline advanced IT tasks such as continuous deployments or zero downtime rolling updates.