Deployment
- Standard term
Deployment is putting a chosen version of your app or service into the place where it runs for its users, such as a live website, an app store, or a test site.
Your laptop holds things the code relies on, such as saved passwords and keys, a local database, and the tool versions you installed. Deploying copies the code to a machine that has none of those unless someone supplies them, so a step can work at home and break the first time it runs live.
Where you’ll meet it
You built an RSVP site for your wedding with an AI assistant, and it worked on your laptop. You deploy it and text the link to a few friends. One replies that the page looks lovely, and that the form shows "Error" when she presses Send.
What to do
Have your assistant compare required settings with the hosting service's Environment Variables and apply authorized missing settings without displaying secrets. It should deploy again and test the live RSVP form. Complete any sign-in or settings step it cannot access, then judge whether the RSVP reaches the intended destination.
Easy to mix up
A release is the moment users get a new feature. A deployment puts the code in place, and that code can arrive switched off until someone releases it.
Check yourself
You deploy a recipe site you built on your laptop. The live pages look just as they did at home, but the list of recipes you saved while building it is empty. What's the likely reason?
Go deeperDatabase changes are the hard part of undoing a deployment
A deployment might upload files the host sends out unchanged, update small pieces of server code that start up only when a request arrives, start a container (an app packaged with everything it needs to run), or submit a phone app for store review. Teams record each one's version, settings, and database changes, because undoing it needs all three.
Redeploying the earlier code usually takes moments. A database change, such as removing a column, can't be undone that way once new data has been written. Careful teams make database changes the old code can still work with, and remove what's no longer needed in a later deployment.