CircleCI alternatives and similar libraries

Based on the "Continuous Integration" category.

Travis

8.8 0.0 CircleCI VS Travis

Free continuous integration platform for GitHub projects.
Concourse

8.7 9.7 CircleCI VS Concourse

Concourse is a container-based automation system written in Go.

Collect, organize, and act on massive volumes of high-resolution data to power real-time intelligent systems.

Promo influxdata.com

fabric8

7.4 0.0 L2 CircleCI VS fabric8

DISCONTINUED. Integration platform for containers.
Jenkins

7.1 9.9 CircleCI VS Jenkins

A static site for the Jenkins automation server
Semaphore

- CircleCI VS Semaphore

Hosted CI/CD service, free for open-source and 100 private builds with native Docker support.
Bamboo

- CircleCI VS Bamboo

Atlassian's solution with good integration of their other products. You can either apply for an open-source license or buy it.
Hudson

- CircleCI VS Hudson

Continuous integration server still in active development.
Codeship

- CircleCI VS Codeship

Hosted services with a limited free plan.
Go

- CircleCI VS Go

ThoughtWork's open-source solution.
TeamCity

- CircleCI VS TeamCity

JetBrain's CI solution with a free version.