Continuous Integration/Continuous Deployment (CI/CD)
A software development practice where code changes are automatically built, tested, and deployed through a pipeline. Continuous Integration merges and tests code frequently; Continuous Deployment automatically releases validated changes to production.
Continuous Integration (CI) is the practice of merging developer code changes into a shared branch frequently (at least daily), with each merge triggering an automated build and test run. This catches integration conflicts early. Continuous Delivery extends CI by ensuring the codebase is always in a deployable state. Continuous Deployment goes further, automatically releasing every change that passes the pipeline to production without manual approval.
Popular CI/CD tools include GitHub Actions, GitLab CI, Jenkins, CircleCI, and Vercel. A typical pipeline includes stages for linting, building, unit testing, integration testing, security scanning, and deployment.
Why It Matters for QA Teams
CI/CD is the backbone of modern QA workflows. Automated pipelines run tests on every change, enforce quality gates, and enable the rapid deployment cadence that makes continuous testing possible.
Example
A developer pushes a commit to a feature branch. GitHub Actions automatically: runs ESLint and Prettier checks, executes 1,200 unit tests, builds the application, runs 80 integration tests, deploys a preview environment, runs 15 E2E smoke tests against the preview, and posts results as a pull request status check. The entire pipeline takes 9 minutes.