RunDeck - RunDeck is an open source automation service with a web console, command line tools and a WebAPI.
Jenkins - Jenkins is an open-source continuous integration server with 300+ plugins to support all kinds of software development
Apache Airflow - Airflow is a platform to programmaticaly author, schedule and monitor data pipelines.
CircleCI - CircleCI gives web developers powerful Continuous Integration and Deployment with easy setup and maintenance.
ifttt - IFTTT puts the internet to work for you. Create simple connections between the products you use every day.
Travis CI - Focus on writing code. Let Travis CI take care of running your tests and deploying your apps.