Travis CI Legacy

Travis CI is a continuous integration service that integrates with GitHub to automatically build and test code on every push. It was one of the first hosted CI services and is widely used in legacy projects. Users define build pipelines in .travis.yml YAML configuration files that specify build steps, testing, and deployment. While GitHub Actions has largely replaced Travis CI for new projects, legacy codebases still use it extensively, and maintaining Travis CI configurations is an important DevOps skill.