CI/CD pipelines for .NET applications. Covers GitHub Actions and Azure DevOps YAML pipelines with build, test, publish, and deploy stages. Load this skill when setting up continuous integration, automated testing, deployment workflows, or when the user mentions "CI/CD", "pipeline", "GitHub Actions",

CI/CD Core Principles 1. Pipeline as code — YAML pipelines committed to the repo. No click ops in the UI. 2. Fast feedback — Build and test on every push. Cache NuGet packages. Fail fast. 3. Build once, deploy many — Build the artifact once, promote it through environments (dev → staging → production). 4. Never skip tests — Tests gate the pipeline. No deployment without passing tests. Patterns GitHub Actions — Build + Test GitHub Actions — Build + Publish Docker Image Azure DevOps — Build + Test Same restore → build → format → test flow as GitHub Actions. Key differences: NuGet Package Publishing Anti patterns Don't Build Different Artifacts per Environment Don't Skip Format Checks in CI Don't Hardcode Secrets in Pipelines Decision Guide Scenario Recommendation Open source project GitHub Actions Enterprise with Azure Azure DevOps Pipelines Docker deployment Multi stage build in CI, push to container registry NuGet library Build → Test → Pack → Push on tag Database migrations Run in CI test stage, script for production Environment promotion Same artifact, different configuration

ci-cd