Shipping backend code without tests means finding out about bugs from your users. Automated tests catch problems while they're still cheap to fix, and CI/CD makes running them, and releasing the code that passes, a routine part of every change instead of a manual chore.
You'll start with the testing pyramid and how unit, integration, and end-to-end tests each play a different role, then look at test-driven development, where you write the test before the code. The rest of the module covers continuous integration and continuous delivery: what a pipeline is, what it automates between a commit and production, and what makes one worth having.
With your code tested and shipping automatically, you'll be ready to think about how it holds up as demand grows in Architecture & Scaling, the next module in this course.
How unit, integration, and end-to-end tests differ, how they fit together in the testing pyramid, and how test doubles like stubs and mocks keep tests focused.
How TDD works and the red, green, refactor cycle: write a failing test, make it pass, then clean up the code.
A fast introduction to DevOps and the basics of continuous integration and delivery, and how a pipeline can improve your productivity and code quality.
A slightly deeper walk through continuous integration and continuous delivery, and what happens at each stage of a typical pipeline.
The basics of continuous integration and delivery, plus the practices that help a CI/CD pipeline succeed in a real team.