I've started using CircleCI to automatically build repos - specifically my various static websites. It's working really well. CircleCI will detect a change to the Github repo, automatically trigger a build and then push the result to the gh-pages branch.
One tip I found useful is to use a machine account to push to the gh-pages branch - this means that we don't need to use our actual github SSH key. You will need machine accounts in [both[(https://github.com/DevProgress/onboarding/wiki/Using-Circle-CI-with-Github-Pages-for-Continuous-Delivery) Github and CircleCI. For each repository that you want to build you need to add the machine account as a collaborator on the Github repository.
CircleCI will also trigger a build on the push to the gh-pages branch which is not what you want. To stop this we need to add [ci skip] to our commit message. In Middleman we can do this by adding deploy.commit_message = "Automated commit at #{time} by #{signature} [ci skip]" to our config.ru.
→ posted on October 2, 2018development