CircleCI Explained: Cloud Pipelines Without Managing Servers
Introduction Jenkins (the batch 25 post) gives you full control — and full responsibility for the server. GitHub Actions (batch 13) gives you convenience — tied to GitHub. CircleCI, launched in 2011, carved out the middle: cloud-hosted CI/CD for any Git host, configured in a single YAML file, with no server to maintain and a generous free tier that made it a favourite of startups and open-source projects. It is the hosted-pipeline idea in its purest commercial form. Jobs, workflows, and orbs CircleCI's model mirrors the other pipeline tools, with its own vocabulary: Jobs — units of work (build, test, deploy) that run in containers or virtual machines, each defined with steps. Workflows — jobs chained with dependencies and filters: run tests on every push, deploy only on the main branch, run jobs in parallel. Orbs — reusable packages of jobs and commands, shared by the community: an orb for Node, Docker, or AWS deployment replaces dozens of lines of config. Config in the rep...