Why is it called Canary deployment?

The term "Canary deployment" comes from the practice of using canaries in coal mines to detect dangerous gases early. Canaries were more sensitive to toxic substances and would die before humans, warning of danger.

In IT, this means gradually releasing a new version of an application to a limited group of users ("canaries") to test stability and the absence of critical errors. If everything is fine, the deployment is expanded to all users.

This approach reduces risks during updates and allows for quick rollback of changes if problems occur.