Developer Documents Key Lessons from Building a First CI/CD Pipeline with Docker and GitHub Actions

A developer learning DevOps built a minimal CI/CD pipeline using Docker, Docker Compose, and GitHub Actions to practice newly acquired skills. The project used a simple Flask API with two routes as a base, keeping the application deliberately basic so the focus remained on the pipeline itself. During setup, the developer encountered and resolved several errors, including a missing requirements.txt file and a Python import failure caused by an incorrect PYTHONPATH configuration. A Docker build context misconfiguration was also debugged, revealing that the build context and Dockerfile path must be set independently when the Dockerfile is not in the project root. The developer also explored GitHub Actions artifacts to persist test coverage reports beyond the lifecycle of a runner's temporary filesystem.