CI/CD stands for Continuous Integration and Continuous Delivery. It is a set of practices that let teams test and ship code automatically. CI runs tests when you write code. CD ships the working code to users.
About 2 min of reading
CI/CD stands for Continuous Integration and Continuous Delivery. I run a small pipeline story, show what happens with only one of the two halves, then catch a bug before it ships so I can see why the two pieces belong together.
A pipeline does the whole job by itself. I print what a teammate hears when they push a change: the tests run, turn green, the code deploys, and finally the update is live for users.
Before you run it, say out loud what it will print. Then open the answer.
CI gives confidence and CD gives speed, but neither is useful on its own. I print what each half looks like by itself and then what they look like joined together.
Before you run it, say out loud what it will print. Then open the answer.
A pipeline stops a broken change before users see it. I write a test that looks for an error in some code and print that the merge is blocked so the bug is fixed in minutes instead of reaching users.
Before you run it, say out loud what it will print. Then open the answer.
Before you write anything, put these lines back in the right order. Click a line to move it up one step. This support step is easier than writing code from scratch, and it is here to make the last example stick.
Read the first example one line at a time. A line that prints shows what appears on screen; the rest set things up quietly.
CI means developers merge their work often. Every merge runs tests automatically. Problems are caught early, before they grow.
CD means the tested code can be released safely at any time. Sometimes it deploys by itself. This is how fast teams ship code.
You: "I changed three files."
CI: "Running tests... all green. Deploying to the test server."
CD: "The update is live for users."No one has to run the tests by hand. The pipeline does it every time. This is the heart of CI/CD.
CI = the tests. It runs every time you write code.
CD = the release. It sends good code to users.
CI without CD: tests pass, but someone ships by hand.
CD without CI: you ship fast, but nobody knows if it works.You need both. CI gives confidence. CD gives speed. Together they let a team ship safely.
A teammate adds a feature but forgets a check. The pipeline runs, the test fails, and the merge is blocked.
That bug would have reached users on their own. Instead, the team fixes it in three minutes. Early feedback is the whole point of CI.